if you're running a four channel, the best way to do it is to run new wires from the amp to the rears, then use the factory wiring to the rears and connect the fronts (from the amp) to it, then connect the front and rears together in the harness behind the radio. that method requires no re-routing of speaker wire to the door. if you're only using a two channel, i'd recommend running new wires to the back of the deck. . .
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