thanks for taking a look for me!, i like to have the car off sometimes with the music on (like the OEM unit would allow). I'm having a hell of a time looking for an accessory wire to allow it to happen though.
the rest of the info you've given is gold though. I did have a feedback problem with the oem amp harness wiring. i ended up making a new ground for it in the trunk that solved all the engine noise/hissing issues.