E36 Stock Stereo Question

In my research, I've found that there seems to be some confusion over the forums I've scoured regarding the sound system in the E36. I have a '92 325i with speakers in the rear deck lid, mids/tweeters in the front doors, and 5-1/4's in the front footwells. I'm assuming the amp in the trunk is a 4 channel, correct? Don't ask about the head unit, that was long gone before I bought the car.

I'm going to replace the amp with an a/d/s P640, and will be using the existing vehicle harness(es). Does anyone have the wiring diagram/schematic for these harnesses handy? I need to identify the speaker output leads and the remote turn on lead. I suppose I could trace them all back to the speakers, but I don't wanna have to take the door/kick panels apart. Lastly, I assume that an amp swap out will be that simple, or am I missing something, given that BMW's are not your ordinary car?

BMWs have the crossovers built into the factory amp. So with your a/d/s you'll have to locate x-overs somewhere. I'll check my schematics and see if I can find anything helpful.

Take it all apart. Come on, its easy and you'll learn more. Takes like 2 minutes to take apart all that cheap plastic.

The schematics are particularly unhelpful for your question. No pinouts shown at all, just colors of wires going to each of the boxes.

Never mind, I found the wiring diagram for everything here in case anyone needs it:

http://www.unofficialbmw.com/e36/stereo/e36_200w_stereo_pinouts.gif

In retrospect, I think taking the car apart might have been faster than sifting through the web to get this diagram, but I think in the end it could prove useful to someone else (although I'm sure this diagram has been posted before).

I love the twisted pair speaker leads that go back to the trunk- for a stock system, it's extremely well engineered! I used them instead of running RCA cables. If your amp can handle speaker level inputs, I recommend this route . . . no difference in sound quality to me, and it makes the install much easier.

Thanks everyone for your help!

Never mind, I found the wiring diagram for everything here in case anyone needs it:

http://www.unofficialbmw.com/e36/stereo/e36_200w_stereo_pinouts.gif

In retrospect, I think taking the car apart might have been faster than sifting through the web to get this diagram, but I think in the end it could prove useful to someone else (although I'm sure this diagram has been posted before).

I love the twisted pair speaker leads that go back to the trunk- for a stock system, it's extremely well engineered! I used them instead of running RCA cables. If your amp can handle speaker level inputs, I recommend this route . . . no difference in sound quality to me, and it makes the install much easier.

Thanks everyone for your help!

That .gif was very useful. It took me ages to get it here.