Morris,

It would be much easier to swap the engine & transmission together from the donor car as long as it has the same transmission in the car that blew the engine. Also, use the axles & check the motor mounts.

If the front end of the donor car was hit, hopefully the engine harness is intact & not cut anywhere. If so, you will need to get another engine harness, unless you want to try to labor through to fix it. Yes you will need to remove the dash to get to part of the engine harness on both cars. Some people say you could use the old harness from the old car, but then have to wire in for the VTEC on the new engine. It can be done, but is usually more of a hassle, with the possilbilty of ruining the ECM if not worked around properly. I would rather spend a little more time to get it done correctly & without any worries of re-wiring something.

Here is a diagram of the wiring harness for the EX coupe:

Hopefully you can see that the engine wiring harness goes through the firewall of the car, so yes, will have to remove or loosen the dash to get to some of the connections. Here some help for the removal of the engine:

Civic

1. Disconnect the negative and positive battery cables. Wait at least three minutes before working around the air bags.

The engine and trans axle are removed from the vehicle as one unit.

1. Support the hood as far open as possible. If the hood is to be removed, first match mark the hinge plates with a felt-tipped marker.
2. Remove the battery from the vehicle. Unbolt and remove the battery tray.
3. Disconnect the battery and alternator cables from the under hood fuse and relay box on the right shock tower.
4. Remove the lower right kick panel to expose the Powertrain Control Module (PCM).
5. Label and disconnect the five wiring harness connections from the PCM.
6. Unbolt the main wiring harness retainer from the rear of the fuse and relay box on the right side of the bulkhead. Carefully pull the grommet out of its bulkhead opening. Next, pull the PCM harness and connectors through the opening. Be careful not to damage the wiring, insulation, or connectors.
7. Relieve the fuel pressure:
   1. Loosen the fuel filler cap.
   2. Use a box-end wrench and a flare nut wrench to hold the fuel filter banjo fitting.
   3. Place a shop towel over the fuel filter to catch the fuel spray.
   4. Slowly loosen the fuel filter service bolt one full turn.
   5. Clean up any spilled fuel.
8. Remove the intake air duct and air cleaner. If equipped, disconnect the Intake Air Temperature (IAT) sensor connector from the air cleaner case.
9. Disconnect the fuel feed hose from the fuel filter. Disconnect the fuel return hose from the fuel rail.
10. Label and disconnect the following vacuum lines:
    • Intake manifold/throttle body vacuum hoses
    • Brake booster vacuum hose
    • EVAP canister vacuum hose
11. Disconnect the Power Steering Pressure (PSP) switch and detach its clamp from the bracket below the brake booster.
12. Disconnect the trans axle ground cable. Remove the radiator hose bracket.
13. Loosen the throttle cable lock-nut, then disconnect the cable from the throttle body linkage. Move the cable aside without kinking it.
14. Loosen the power steering pump mounting bolts. Slip power steering belt off its pulleys. Unbolt the steering pump and move it out of the work area. Don't disconnect the hydraulic hoses.
15. Label and disconnect the engine wiring harness connectors at the left side of the engine compartment.
16. Drain the coolant from the radiator and engine block.
17. Disconnect the upper and lower radiator hoses, then remove them. Disconnect the heater hoses from the cylinder head.
18. If equipped with a CVT trans axle, loosen the shift cable lock-nut. Remove the spring clip and washers and disconnect the shift cable from its linkage. Be careful not to kink the cable or damage its boot.
19. If equipped with a manual trans axle, unbolt the hydraulic line brackets from the top of the trans axle case.
20. Attach a chain hoist to the engine lifting brackets. Don't raise the hoist to lift the engine yet.
21. Raise the vehicle and support it safely. Remove the front wheels.
22. Remove the engine splash shield.
23. Drain the engine oil.
24. Drain the fluid from the trans axle.
25. If equipped with A/C, unbolt the left front engine mount bracket from the shock tower.
26. Loosen the compressor idler pulley and adjusting bolt. Slip the belt around the engine mount stud to remove it.
27. Unbolt the compressor mounting bolts to separate the compressor from its mounting plate. Move the compressor out of the work area. Do not disconnect the A/C refrigerant lines.
28. If equipped with an automatic trans axle, disconnect the ATF cooler lines. Plug the cooler lines to prevent fluid leakage and contamination.
29. If equipped with a manual trans axle, unbolt the slave cylinder from the trans axle case without disconnecting its hydraulic line.
30. Separate the front exhaust pipe from the exhaust manifold and catalytic converter. Unbolt its hanger bracket and remove the exhaust pipe.
31. If equipped with an automatic trans axle, disconnect the shift cable from the trans axle control shaft.
32. If equipped with a manual transaxle, disconnect the shift rod and extension rod from the transaxle.
33. Unbolt and remove the strut damper fork. Disconnect the steering knuckle ball joint from the lower control arm using a ball joint separator.
34. Pry the inboard CV-joints from the transaxle. Then, move the half shafts away from the transaxle and wire them to the undercarriage of the vehicle. Tie plastic bags over the inboard CV-joints to prevent damage to the boots and splined shafts.
35. Raise the hoist slightly to take up the weight of the engine and transaxle assembly.
36. Disconnect the engine mounts in the following order:
    1. Unbolt and remove the left front engine mount.
    2. Unbolt and remove the right front engine mount and bracket assembly.
    3. Remove the rear engine mount through-bolt. Then, unbolt the rear mount bracket from the engine block.
37. If necessary, lower the vehicle slightly to gain access to the side engine and transaxle mounts. Do not release the tension of the chain hoist-the engine must be securely supported.
38. Unbolt the side engine mount bracket from the engine block bracket and mount damper.
39. Unbolt the transaxle mount bracket from the transaxle case. Then, unbolt the mount from the shock tower.
40. Raise the chain hoist to lift the engine a few inches off of its mounts.
41. Verify that all electrical, vacuum, and fuel lines have been disconnected.
42. Raise the engine and transaxle assembly and remove it from the vehicle.

To install:

Use new self-locking nuts and gaskets when installing the front exhaust pipe and when assembling the front suspension. Use new set rings on the inboard CV-joint splined shafts.

1. Lower the engine and transaxle assembly into the vehicle.
2. Install and connect the engine and transaxle mounts and brackets. Use new self-locking nuts and color-coded bolts. At this point, only tighten the mounting nuts and bolts by hand.
3. Before installing the left front engine mount, fit the A/C compressor back into place and install the compressor belt. Tighten the compressor bolts to 17 ft. lbs. (24 Nm).

Failure to tighten the bolts in the proper sequence can cause excessive noise and vibration and reduce bushing life. Be sure to check that the bushings are not twisted or offset.

1. The engine and transaxle mount and bracket fasteners must be tightened in the proper sequence with the weight of the engine resting upon them. This step is important for engine mount pre-loading. Tighten the engine mount bolts in the following sequence:
   1. Transaxle mount bolts: 47 ft. lbs. (64 Nm); or 28 ft. lbs. (38 Nm) for CVT-equipped vehicles
   2. Side engine mount bracket nuts: 54 ft. lbs. (74 Nm)
   3. Rear mount bracket bolts: 61 ft. lbs. (83 Nm); or 43 ft. lbs. (59 Nm) for CVT-equipped vehicles
   4. Rear mount through-bolt: 43 ft. lbs. (59 Nm)
   5. Transaxle mount bracket nuts or bolts: 47 ft. lbs. (64 Nm).
   6. Transaxle mount through-bolt: 54 ft. lbs. (74 Nm).
   7. Right front mount bracket bolts: 33 ft. lbs. (44 Nm).
   8. Right front mount carrier bolts: 33 ft. lbs. (44 Nm).
   9. Left front mount: stud: 61 ft. lbs. (85 Nm); carrier bolts: 33 ft. lbs. (44 Nm); nut: 43 ft. lbs. (59 Nm).
2. Remove the chain hoist from the engine lifting hooks.
3. Install new set rings on the inboard splined shafts of each half shaft. Check that the set ring on each inboard CV-joint clicks into place when the half shafts are installed into the transaxle.
4. Install the damper fork and reconnect the lower ball joint. When the weight of the vehicle is resting on its suspension, tighten the pinch bolt to 32 ft. lbs. (44 Nm) and the fork bolt to 47 ft. lbs. (65 Nm). Tighten the ball joint castle nut to 36-43 ft. lbs. (50-60 Nm). Next, tighten the castle nut only enough to install a new cotter pin.
5. If equipped, install the slave cylinder. Tighten the slave cylinder mounting bolts to 16 ft. lbs. (22 Nm). If the clutch hydraulic line was disconnected, air must be bled from the system.
6. If equipped, reconnect the transaxle shift and extension rods to the linkage at the transaxle case. Install a new 8mm spring pin into the shift rod linkage. Then, install the retainer clip and boot. Tighten the extension rod bolt to 16 ft. lbs. (22 Nm).
7. If equipped with an automatic transaxle, connect the shift cable to the control shaft. Use a new lock washer and tighten the lock bolt to 10 ft. lbs. (14 Nm). Tighten the shift cable cover bolts to 16 ft. lbs. (22 Nm). Install the shift cable cover and tighten its bolts to 16 ft. lbs. (22 Nm).
8. Install the front exhaust pipe using new self-locking nuts.
   • If equipped with the D16Y8 engine, tighten the converter flange nuts to 16 ft. lbs. (22 Nm). Tighten the exhaust manifold nuts to 40 ft. lbs. (55 Nm).
   • If equipped with the D16Y5 or D16Y7 engine, tighten the converter flange nuts to 25 ft. lbs. (33 Nm). Tighten the exhaust flange bolts to 16 ft. lbs. (22 Nm).
9. Reconnect the ATF cooler lines. If the rubber cooler lines are cracked or stressed, they must be replaced.
10. Install the engine splash shield.
11. Refill the engine with fresh oil.
12. Refill the transaxle with the proper fluid.
13. Lower the vehicle.
14. If equipped, fit the clutch hydraulic line brackets back into place. Tighten the 8mm bolts to 17 ft. lbs. (24 Nm). Tighten the 6mm bolts to 8 ft. lbs. (11 Nm).
15. If equipped with a CVT transaxle, Reconnect the shift cable to the linkage. Use new plastic washers and a new spring clip. Tighten the lock-nut to 22 ft. lbs. (29 Nm).
16. Adjust the alternator and A/C compressor belt tensions.
17. Install and reconnect the upper and lower radiator hoses. Reconnect the heater hoses.
18. Install the power steering pump into its mounts. Adjust the pump belt tension, then tighten the mounting bolts to 17 ft. lbs. (24 Nm).
19. Reconnect the PSP switch connector and attach its harness clamp.
20. Reconnect the following vacuum lines:
    • Intake manifold/throttle body vacuum hoses
    • Brake booster vacuum hose
    • EVAP canister vacuum hose
21. Reconnect the fuel line fittings to the fuel filter and fuel rail. Use new sealing washers. Tighten the banjo fittings to 25 ft. lbs. (33 Nm), and the service bolts to 11 ft. lbs. (15 Nm). Don't over tighten the fittings.
22. Reconnect the throttle cable and adjust its deflection to 10-12mm (0.39-0.47 in.).
23. Feed the PCM harness through the hole in the bulkhead. Apply sealant to the grommet, then install the retainer.
24. Reconnect any engine wiring harness and ground cables that were disconnected during engine removal. Be sure the grounds are free of corrosion to ensure good contact.
25. Fit the fuse and relay box back into position. Reconnect the battery and alternator cables.
26. Install the air cleaner case and air intake duct. Reconnect the IAT connector.
27. Reconnect the five PCM connectors. Install the kick panel.
28. Install the battery tray and the battery.
29. Verify that all wiring harnesses and grounds, vacuum lines, fuel lines have been reconnected.
30. Refill the radiator with fresh coolant.
31. If it was removed, install the hood. Reconnect the windshield washer tubing. After installation, check to be sure that the hood, fender, and grille panel gaps are equal.
32. Reconnect the positive and negative battery cables.
33. Turn the ignition switch to the ON position, but don't start the engine. Then, turn the ignition OFF. Repeat this procedure two or three times and check for fuel leaks.
34. Start the engine and allow it to warm up to its normal operating temperature.
35. Bleed the air from the cooling system with the heater valve open.
36. Check the throttle cable deflection and operation.
37. Check and adjust the ignition timing.
38. Shut the engine off and check the drive belt adjustments.
39. Check all fluid levels and top up as necessary.
40. Check and adjust the front wheel alignment.
41. Road test the vehicle.

I will try to see if I can get a diagram for the dashboard for you also. It should be straight forward, but any other questions, please feel free to ask. Thank you.

Wes