I have a 2005 Nissan Pathfinder SE. Recently I damaged the liftgate when backing into the gate to my driveway. I bought a used liftgate of a like kind vehicle. My question is do I wire the replacement liftgate wiring to the vehicle or use the current vehicle liftgate wiring harness connecting it to the replacement liftgate? If I use the replacement liftgate wiring how do I access that area on the driver side c pillar to be able to plug it in? I do not know how to access the area in the headliner. Not sure which trim panels to remove or how to remove them in order to plug in the wiring harness on the replacement liftgate to my car. I hope I was clear :-)

Whichever is easier, if you remove the harness inside the new liftgate you are looking at close to the same issues. If the 'new' harness has been cut to get it out of the donating vehicle quicker of course you won't use that. The one already in car should be proven out to be good.

Use the existing wiring and see if it will work. Thats the first step.