I just bought a '97 Z28. I am looking to upgrade to power windows and rear window with a defogger. Was a complete harness wired for all or most accessories installed in the '97s, or where several harnesses installed depending on options installed?

When I go to power windows, if the harness is not already in place, it won't be much of a problem wiring them up. The rear window is a different story. Anybody have any ideas? Thanks.