Wow, what a mess. The dealer's estimate is probably not too far off. Your car has 14 pairs of speaker wires, so they could have potentially made spaghetti or the factory wiring to connect that turd of an aftermarket amp.

There were three plugs on the DSP amp: a big 15-pin plug, a medium-sized 26-pin plug, and an 18-pin plug. It looks like only the 18-pin plug remains (from the picture). Be sure to get the other two plugs.

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