Re: AC Problem!?
If you stick with R12, the AC is going to be expensive.
As for the window, here is a couple of things to look for. First check the fuse under the dash. If it is good, check for power at the switch in the cab. Does the fuse blow if you use the switch? Yes-Shorted circuit. No-open circuit. Some how you have to get the back window down. What you can do is climb back there and open the access panel. You will then have to run power to the motor directly. What I did was drag a second battery back there and touched + to one of the two motor wires and - to the other. If nothing happens at all, bad motor. If it either tries to move up or down, change polarity on the wires to make it run all the way down. Now you can get to the motor, safety switches and harness better. Now you just have to troubleshoot the circuit as normal. One common problem is from the tailgate opening and closing over the years, the wire harness between the gate and body breaks. Inspect that very carefully. If you need more detail, I can e-mail a guide.
If it ain't broke, I can probably still fix it.