The little gas props on my rear window have quit working. Before I ordered new ones, I decided to see what was involved in replacing them. On the upper end, there is a hex shouldered ball that appears to screw into the window frame, so I proceeded to remove it (with some difficulty). BAD IDEA. It screws into a nut on the inside that is NOT a captive nut. By pulling out on the stud as I unscrewed it, I finally managed to get it unscrewed and of course the nut was now free and lying inside the window frame which is glued to the window. By drilling a 1/8 hole in the plastic close to the hole, and using a small screwdriver with a long blade I finally managed to position the nut on the hole and prying to hold it tight, got the stud started threading into it. Since the stud was obviously not meant to be removed, I assumed the strut must be able to be popped off the ball, but if it is, I can't find the secret. Has anybody replaced these struts, and if so, HOW??