I misread your last post about the cd goes in trunk and MID in the glovebox. I think I can do this now. Thanks for the help I will keep you posted.

How did you get the connection for the headunit thats in the dash to use in the back to hook up the cdplayer/radio? Did you have to cut the one off up front and wire the wires manually to the radio or what did you do?

@OP, your aftermarket head unit can only power 4 speakers, if you have DSP most likely you have 8 speakers + the 2 6.5" subs on the rear passenger compartment. I kept the factory speakers in, used an Alpine 4x100W amp to power all 8 speakers. I did NOT run speaker wires to each speaker, instead the DSP AMP in the back has speaker wires all there, you can splice into there and run to your amp literally with less than 3 ft of speaker wire to tap into your aftermarket Amp which can be mounted directly in place of the DSP AMP or above it if you find a small enough amp like me. You only then need to run a set of RCA's up to the aftermarket HU or 2 sets if you wish to fade. I ran one and used a splitter at the AMP. I bypassed my DSP amp alltogether since it died due to water intrusion.

Anywhere that actually has the right colors as far as speaker wiring goes? Like which one is right rear negative, and so forth.