[C10 - C90 Bill]

The 8500 and 9500 Cabs are the same, but I don't believe the Split Glass Windshields they have will work in a 7500 that has the 1-Piece Windshield. Maybe Dan or Bob can jump in to let us know either way for sure.

I would also try the find the original GM part number for it. That should help in your search as well as the interchange.