when i pulled my stock radio out to switch in the pioneer i also noticed a mess of wires. My suggestion to you is forget all that crap and run a 4chan amp to your door speakers and rear speakers. that way all you have do do is run 2 sets of rca cables from the head unit to the amp and the wire the speakers to the amp. Also, this plan will produce much clearer sound. This was my plan until the stuff got stolen out my car one night before i even installed it