Unless you are intimately familiar with and fully capable of re-installing the electrical components, I'd advise against that. Do whatever you want to the exterior (if you don't care about its resale value) but don't monkey with the electronics yourself unless you absolutely know what you're doing.
Seconding what Lon and Johnny said. Over time, the insulation on the wires can become brittle, and removing the harnesses can create all sorts of problems. Hell, even missing one ground when hooking it all back up can cause some really difficult to pinpoint faults.
I agree with Lon, Marko, and Strathdam, have it done professionally. Better to pay to have it done right and look amazing, than DIY and have it look good, but not sound right. I always make the 150 mile trip to Guitar Center in Salt Lake City, Utah to have mine worked on at least once every 4 to 5 months. I drive a ‘94 Geo Metro, so gas isn’t a problem because the car gets 52mpg.
