Quote Originally Posted by wild2crazy View Post
No gmos for me. just the radio adapter I Don't need the gmos adapter because my car does not come with onstar or chime functions still work without it so its a basic hook up to keep my bose amps running.
Metras vss01 is the only proper working harness out there for non on star bose systems for 97-03. but thats a seperate amp for crossovers/and fades to work.

Pioneer radio requires only the 12v sources from the parking brake on to unlock some feature and the 12v on for the reverse light on which would activate my back up camera. If not i would have to activate it manually on the head unit to see reverse mode.

I probably could go right into reverse light bulb harness itself and it would accomplish the same feat but that would require running a wire all the way to the back but if the bcm main connect is right there it should be a easy tap into. under the steering wheel. same should go for the parking brake foot pedal switch i would just remove the pin and crimp the wire into the bcm harness.
You may want to double check the parking brake lockout. On my first Pioneer head unit, grounding that lead did the trick. On the Z150 head unit I have now, it involved tapping into a wire on the other connector, then grounding the two.

What year GP do you have? When I get a chance, I'll see if I can find what you're looking for. The radio wiring across those years are basically the same. The BCM harness I'm not so sure about.