Hi, I have a 2004 GP GT with what I believe to be the plain factory stereo and amp in it. I took the Alpine head unit out of my old Grand Am and I'm looking to install it in my GP. I have a GMOS04 adapter that Crutchfield says is the correct harness/adapter and the sound goes through the factory amp. The thing is the power from that adapter/head unit are too much for the factory amp, and when I turn up the head unit to roughly 1/2-3/4 the sound will cut out. There are small turntable adjusters on the GMOS04 but it will still cut out when I turn up the head unit. I'm wondering where the factory amp is at in my car and if it has adjustable inputs on it. I already looked in the trunk between the 6x9s and didn't see it and I figure I would just see if anyone here knew where it was.