get a low powered aftermarket amp, use that, as far as the wires, they make wiring harness' that you would use for an aftermarket headunit(for the weird people who use those, jp) this plugs into the plug that would have gone to your stock headunit, so you don't have to cut any wires at all. Much like
this one, however, I don't know your car year, or if you have the monsoon system or not for deff.