So whatever jack wagon owned my disco before me completely messed up all the stereo wiring. They bi-passed the amp and just wired everything directly to the head unit. I know that this is a common fix as the factory amps tend to be garbage, but the subwoofers in the back no longer work. I'm also not entirely sure if either the amp beneath the passenger seat or the one behind the subwoofer works.

So I have a few questions.

-Does anyone know which color wire is what for the main amp wiring harness?

-Does anyone know of a way to test to see if the amp is still working, for both the main and the sub amp?

-Assuming the amps still work, is it better to just rewire the whole thing or is it better to try and salvage what is left?

-Assuming the amps do not work can anyone recommend a head unit powerful enough to run the subs with full quality or a recommendation for an amp that goes well with the disco and the factory sound system?

Any help is much appreciated, thanks in advance!