I Have A System Ready To Install

[ArmyofOne]

about the ES250 Electrical System. in my contour, since i didnt have a factory amp, i used stock speakers in the 4 doors, used a Pioneer DEH 1550 HU in the stock location (no kit needed) and ran my wires down the sides of the car. i have a 12"Alpine sub and a pretty standard box that it sits in. also have a Jensen A34XP amp with 170 RMS. i knwo its not a lot fo power, but in the contour it worked great. now how do i go about installing all of this in my lexus???