Another K5 rear window thread

[tobiahr]

I have a 1982 k5 with a power rear window that is stuck in the up position. there is a sub box built and mounted to the rear floor so that it is snug against the back door and I cannot get to the panel and roll down manually or reach the motor. the rear window will not roll down with either the dash switch nor the tailgate switch and there is power to the dash switch. can anyone tell me what wiring I can cut into to try and bypass the switches or it that is even possible? kinda stuck at this point and looking for any suggestion that does not involve destroying the sub box or body sheetmetal.