I just recently completed this task and it took a bit longer than I wanted. However, it is done, the re-manufactured motor is in and the window works and the OEM is headed back for a core charge rebate.
I did everything BUT remove the glass, though I did try that route for a while. I wanted to remove the motor and slider assembly, but the only way to do that is through the top of the door. This means removing the glass. That wasn't happening with the bolts and everything holding the glass to the slider. So, I went a different route.
With a screwdriver bit and a mirror, I removed the three screws that hold the motor to the assembly and popped it out through the speaker hole. I also loosened the 4 bolts that hold the assembly to the inner door skin in order to pry the motor from between the assembly and the door skin. You can't get the motor out without pushing the assembly towards the outer door skin, and this cannot be done without removing/loosening the 4 bolts that hold the assembly in place.
A bit of finagling with the new one, some bumping of the motor to get the gears to seat correctly and everything went back together perfectly.
This was after two days of removing bolts, nuts and other parts and trying to get the square pieces out of the round holes. Without removing the glass, there is just no easy way to remove the whole assembly. With the window pulled all the way up (which was something I could do by hand, not sure if others are similar) I had zero risk of the spring giving me any issues. It only helps pull the window up, so with the window up, the spring is not exerting any force on the assembly.
It took some extra time, but just removing the three screws and the 4 bolts that hold the assembly to the door skin proved the best route.
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