I just changed my passenger door glass on my 88 coupe, and ran into a problem that I thought I would share since I could find nothing in a search. My manual said after removing the door panel and three bolts, in order to remove the window stop, and I "might" need a window stop removal tool to remove it. A little understatement here. What they mean is, when you turn the allen wrench on the stop (a cone shaped nylon roller about 1 1/4 inch long near the bottom front of the window) the flat washer/nut combo on the back you can't see or get to, turns also since locktite was used at the factory. This yellow locktite is really strong. So it won't loosen or come off. You can't get the window out without removing it.
What I did is slide the window on an angle (rear up) towards the rear, until the studs align with a cutout in the top metal inner door panel. There are two right above each other, and one more in the middle of the window. They will slide through, leaving the window stop exposed near the regulator. I purchased a used window, and it had the stop attached so I put it on a table and eventually got it off with vise grips on the washer side. Since my old window was headed for the garbage can anyway, I didn't care if I broke it, but dreaded the mess. So I put a long socket just big enough to fit over the end of the stop, added a long extention, and moved it up and down, bending the threaded metal rod until it broke off. Apparently the tempered glass is stronger than the 1/4 inch threaded rod.
I duct taped the stop washer/nut combo thing in place on the new window, slid it in, and aligned the three holes in the carrier. It tighened up just fine
I was amazed how hard I had to hit the old glass with a hammer to break it up in the garbage can. That is tough glass. Hope this helps someone.