For the rear window motors, I did not want to remove transmissions since that would mean regulator removal. I just removed the motors. They are held on with two 3/8" nuts on through studs. The top nuts are easy to reach, the lower ones are tough. With a long 1/4" drive extension, working blind, you can get to the nuts. I am not sure how easy re-assembly will be.
Reassembly of the rear motors was indeed an adventure. We have a video. After I had the motors installed, it occurred to me that if some of the sheet metal was drilled or cut away, access would be greatly improved.