You will need to remove the instrument panel in order to replace the heater core:
Fig. Fig. 2 Remove the bulkhead electrical connectors from inside the engine compartment
Fig. Fig. 3 Remove the audio unit ground and the GEM/CTM ground bolts
Fig. Fig. 4 Remove the instrument panel bolts through the steering column opening
Fig. Fig. 5 Remove the passenger side ground bolt
Fig. Fig. 6 Detach the passenger side instrument panel main harness connectors
Fig. Fig. 7 Remove the instrument panel bolt on the relay bracket
Fig. Fig. 8 Remove the instrument panel bolts through the passenger side air bag module opening
Fig. Fig. 9 Remove the instrument panel reinforcement bolt below the driver's side corner of the glove compartment
Fig. Fig. 10 Position the carpet aside and loosen the instrument panel floor brace
Fig. Fig. 11 Remove the passenger side instrument panel cowl side nut
Fig. Fig. 13 Remove the cowl panel mounting bolts
Fig. Fig. 14 Remove the instrument panel
The AFCM is attached with velcro.
CAUTION Carry a live air bag with the bag and trim cover pointed away from your body. An accidental deployment will then deploy with minimal chance of injury. Place a live air bag on a bench or other surface with the trim cover up.
Two people are required to perform this step.
To prevent any squeaks or rattles, install and tighten the upper instrument panel floor brace bolt first, then tighten the floor brace bolts and nut.
Install the passenger side bolt first.
CAUTION Never probe the connectors on the air bags. Doing so may result in air bag deployment, which could result in personal injury. Carry a live air bag with the bag and trim cover pointed away from your body. An accidental deployment will then deploy with a minimal chance of injury.
Fig. Fig. 2 Remove the A/C plenum demister screw and remove the A/C plenum demister adapter
Fig. Fig. 3 Disconnect the vacuum line
Fig. Fig. 4 Remove the heater core bracket
Fig. Fig. 5 Remove the 13 retaining screws and remove the plenum chamber top
Fig. Fig. 6 Remove the heater core
CAUTION Never open, service or drain the radiator or cooling system when hot; serious burns can occur from the steam and hot coolant. Also, when draining engine coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze and could drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantities. Always drain coolant into a sealable container. Coolant should be reused unless it is contaminated or is several years old.
Well labor rates vary from shop to shop, each according to its needs to meet overhead.
But expect to be charge 8hrs labor for the job. With labor rates varying from $60 per hour on low end and $130 per hour on high end, expect to pay between $800 to $1100 parts and labor for a shop to do the work.
It can be done at home in a weekend. Nothing very difficult, just time consuming, and at times hard on the back as you are working in and under the dash to remove it.