The direction I want to go based on the feedback regarding the factory amp is to acquire a better 6 channel amp and wire in the unconnected factory rear speaker kit and mount the new amp to factory bracket. The door and dash speakers may not be original- they sound good
. I still need to investigate that. May be able to disconnect factory DSP and replace with some cup holders since that will be moot if i move away from factory amp. I don't want to go back to the stock unit, I plan to keep the Alpine for now and get all 6 speakers playing. If anyone has a resource identifying speaker wires coming out of factory amp I would appreciate you sharing it with me. Seems like mating the Alpine head unit to an Alpine amp might be the best. I appreciate all the feedback!