Just picked up the 18187 Draw-Tite Trailer Light Module for my '02 XC70. I want to mount it inside the Tailgate and drap the Trailer Plug through the liftgate as required. I do not tow very often, but when I need to want the harness availale. My plan is to stuff the module behind the drivers side rear compartment and pull out as required. A couple of questions:

1- Is the XC70 a 2 wire system or 3 wire system? From what I understand, is a 2 wire is the brake and turn are the same bulb......and a 3 wire the brake and stop are different.....

2- Does anyone have the break down of what wire is what back there in that huge bundle of wires???

3- Is that grey connector with the one red wire + Battery and not used for anything?

Thanks