I acquired an 87 K5 about 7 months ago and have been putting off fixing a problem with the rear window/tailgate. The back window won't retract into the tailgate (it's electrically actuated). I removed the cover off the tailgate to gain access to the linkage, and the motor turns with the cable disconnected, but I can't get any of the gears to budge. Is there a way to tackle this problem without taking the top off? The rear window has some cracks in it that are beginning to spiderweb, so I'm a little weary of trying to use any force on the window itself. I'm on a real budget with this truck (low-ranking enlisted in the USAF), so I'm trying to avoid having to do things like taking the top off (I'd have to replace all the seals with how old they are).