I'm trying a different arrangment for installing power windows in the GMC than I used in the Studebaker. This one is pretty neat...uses the factory regulators but installs an electric motor and transmission inside the door to drive the input shaft spline. Seems the instructions have you leave the spline as is, and they furnish some sort of cap to put on the inside in place of the factory crank, but we took the unit apart and trimmed the spline down to the minimum length it needed to be for the drive mechanism, which will allow a nice flat inner surface. Looks like it should work nice...
I bought them from an Ebay store for $89...Spal's website lists that kit at $149. Seems to be a pretty well designed and built product... http://www.spalusa.com/store/main.aspx?p=itemdetail&item=33000031
I really like these. Seem to be a considerably better design than the push-pull cable type I put into the Studester. These work very well, quick and positive. I'd sure recommend them- tjs
I had bought a unit very similar to those awhile back. It was a very simple install but as I soon discovered, mycranks were shot, so it was a struggle to get the windows up. I just bought a setup off Ebay of the ones made by Dolphin. Hope these work better for me.