Does it already have preouts? I searched the archives and could not find a radio diagram or a FAQ on amplifier installation. A friend of mine seems to be pretty good w/ installing amplifiers etc and I am going to allow him to work on my car. My question is, do I need to pick up something called an "S&I" adaptor or anything else before getting started. This is going to be an after work thing and the stores will be closed by the time we tear out the radio.

There are pre-amp outs. you do not need an adaptor as such. There is a pre-amp out plug (probably already attached to the back of the unit, if not, you'll find it in the harness behind the unit). You'll need to cut the wires, leaving a few inches, & solder rca connectors to the ends to mate with the amp wires. As a less desirable alternative, you can open the unit & solder direct to the pre-outs.