I am having a problem adjusting the passenger side rear quarter window. The back end (closest to the roof) is lower than the front by approximately 1/4 inch. The window travels correctly up and down. I have looked at the Fisher Body Service News #15. It tells how to adjust the window, but it is not working. The drivers side went in and was near perfect with little adjusting needed. Anyone gone thru this frustrating task? Can you share any information? Thank You.