yes it will be easiest to get all wires at the headunit. are you planning on just getting signal there and then running new wires from the amp to the speakers or running back through the factory wires? also does the 4 channel amp have a preout on it? if so then you can get rid of the existing loc and run signal from that to the sub amp.
2013 F150 4x4 SCrew XLT 5.0L
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