Basiclly I want to install a new headunit while still using the entire mach 460, including the two amps in the back and speakers. But also I want to be able to install another amp and subwoofer in my trunk. To me this sounds like a pretty decent idea, I would be able to keep my highs on my tweeters, my mids from the back amps, and then have lows that are controlled through the aftermarket HU. Here's the complications though. I've never worked with sound systems before, ever(I'm 17). There was once an aftermarket headunit in my car that was stolen out years ago so the wires were then plugged back into a stock headunit. This means that the wires are all cut behind the headunit. There was also a bypass originally done, I undid this and returned the amps back to working so I doubt this'll effect anything(just a note). At a point though RCA cables leading from headunit to trunk were laid, along with a power wire to the battery, and a blue(I guess system control wire?), to the head that aren't in use. Sooooo, I figure this can be used for the aftermarket amp and sub. To the questions(!): Is it possible to keep intact the stock 460 amps with an aftermarket HU? If yeah, how can I do this? How many preamps would I need in my headunit? Well, I guess I didn't have many questions. That was about it, I believe. Oh and this is in a 1995 GT.