Whats up guys, so I got a Z2 for my Gs300, and I currently have a after market amp installed in the trunk for my subs. I still use the factory amp, and cd changer, but obviously am going to lose that once installed. My questions pretty straight forward, ive seen a few methods of installing the head unit and by passing the factory amp Via making a harness with two of the Metra 70-1761 kits, one at the stock amps end, and the other to plug "directly" into the avics harness... sounds simple right? pretty straight forward? well, yea, not when you got this all, and know almost nothing about radio i