[brcidd]

Sometimes it is just as easy as looking at another vehicle-- I'd look for used Envoys on the lot and pretend to want to buy it, while popping the hood and getting all the info I need about the fusebox, including photos. Any reputable dealer would allow this- also recking yards and any friends who drive an Envoy.

I once had a vehicle where the fusebox wiring harnesses were in backwards, having the starter wire circuit directly into a fuse that only blew when overloaded by the a/c....left me stranded for several hours before I figured it out....the car had been in a body shop and their "ace" mechanic swapped the hot lead wires- went and looked at another vehicle and soon discovered the difference.......