Where are the amps and how do i by pass them for the stereo

The amps are located inside the radio. Most in-dash receivers that provide for "pre-amp outputs" also called "low level outputs" do so by providing female RCA type jacks. These are often found at the end of a short (4 - 6 inch) cable and are usually color coded red & white or red & black (some receivers provide a yellow RCA jack for video in / out, too). To use these RCA audio jacks, you need to realize that one jack is for the left channel source and the other is for the right channel source for a stereo signal. You will have to connect a compatible plug and cable of enough length to extend to a remote amplifier's RCA input jacks. The vehicle's speakers would also need to be connected directly to the same amplifier's output terminals. Using the two audio (left and right) RCA jacks will only allow the radio to control balance of the left and right audio, no fader (front and rear) control is possible. To get fader control, you'd have to either have a radio with four RCA low level output jacks (front L & R *and* rear L & R), or use the radio's speaker (or high level output) wires and connect them to the amplifier's speaker (or high level) input terminals.

All unused receiver wires should be terminated in a wirenut or securely wrapped in electrical tape to prevent accidental contact with grounded metal or other wires behind the dash.

I hope this helps!