i just installed a sub and an amp last week. Took me about 5 to 6 hours. I kept the stock deck (steering wheel control
) and just hooked up from the rear speakers to the speaker level inputs on my amp. There is a factory grommet in the firewall and you will need to remove the panel under the glove compartment to access it.
The most pain in the a** part is to remove the little plastic plug which plugs the hole in the grommet(you actually have to pull the drain pipe from the windsheild out of the way in oder to see it). With the battery in place, it was hard to get a good grip on the tip of the plug and pull it out . It's in there pretty tight too. I scractched the sheet metal wall a few times when loosing grip. If you can want to spend time and remove the battery, I beleive it would be so much easier. From there on, it is pretty simple. Pull the wire thru the firewall, down the right passenger side and along the bottom of the door well which comes off if you pull it. In order to do a clean install, I had to remove the seat belt anchor at the bottom and pull up the panels a little and run the wires under there, under the rear seats and under the trunk floor. The trunk floor can be removed if you look around and detach all the screws and clips.
I did a pretty clean install. If you sat in my car, you wouldn't know that I
had a sub installed until I cranked it up!! If you guys need any more info, just let me know.