The injectors on that engine are really easy to change. The fuel rail is held down by four bolts, 2 on each side. On the side that you want to change, just remove the two bolts holding the fuel rail to the intake manifold. The injector is just held in place by a couple of o-rings.
However, we don't really have an injector problem on that engine. Why are you wanting to replace an injector?
Here is the procedure from the shop manual:
Relieve the fuel pressure; refer to Section 310-00 .Partially drain the cooling system; refer to Section 303-03 .Remove the power steering reservoir bracket. Remove the three power steering reservoir bolts.Remove the power steering reservoir bracket.Remove the accelerator control splash shield. Remove the three accelerator control splash shield bolts.Remove the accelerator control splash shield.Disconnect the fuel pressure regulator valve vacuum hose.Disconnect the fuel lines; refer to Section 310-00 .Disconnect the four RH fuel injector electrical connectors.Disconnect the four LH fuel injector electrical connectors.Disconnect the heater water inlet tube hose. Release and move the hose clamp.Disconnect the heater water inlet tube hose and position aside.Remove the brake booster bracket and tube. Remove the brake booster bracket nut.Release and move the two hose clamps.Remove the brake booster tube.Remove the positive crankcase ventilation (PCV) hose.Disconnect the exhaust gas recirculation (EGR) valve to exhaust manifold tube. Disconnect the two differential pressure feedback EGR (DPFE) transducer hoses.Remove the EGR valve to exhaust manifold tube upper fitting.Remove the EGR valve to exhaust manifold tube lower fitting.Disconnect the EGR valve vacuum hose.Disconnect the PCV by-pass hose.Disconnect the idle air control (IAC) valve electrical connector.Disconnect the (DPFE) transducer electrical connector.Disconnect the vapor management valve (VMV) hose.Disconnect the Vacuum Hose from the RH upper intake manifold.Disconnect the RH radio ignition interference capacitor electrical connector.Disconnect the LH radio ignition interference capacitor electrical connector.Remove the LH fuel injection supply manifold bolts.Remove the RH fuel injection supply manifold bolts.Remove the (A) fuel injectors from the (B) fuel injection supply manifold (9F792).Inspect and replace the two O-rings from each fuel injector, if needed.Shift and remove the fuel injection supply manifold.