I have completely bypassed the Monsoon amp and have all new speakers (Alpine 6.5" coax in doors, JL audo 4" in hatch). I wired up my Blaukpundt headunit using a wiring harness from Crutchfield. I didn't even attempt to use any of the factory wires to wire my speakers. I ran all new wires for the 4 speakers. When I install my 300/4 JL Audio amp, I plan to use all new wires to hook up everything to it. So you don't need a single wire off your factory harness to hook up your amps. The wiring setup is fairly straightforward for the headunit. There are the usual power leads, ground, accesory, antenna, etc.