I answered your PM, but here it is for someone else might need the info:
The easiest way is to run new wires from the headunit to the factory amp and use the output (to the speaker) side wires to run into the doors, etc. Its kind of a pain, but if you are keeping the car, I'd go ahead and do it once and you wont have to do it again.
-There are 10 kinds of people. Those who understand binary, and those who do not.
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