Scott,
The new rear window gasket I got from Steele Rubber did not have the holes for the screws nor were the ends vucanized. I cut the gasket to fit the glass, taped the gasket to the glass and then placed the glass/gasket assembly in the cab opening. I made sure the assembly was centered adequately, and then had someone mark the screw hole locations from inside the cab. Once I had the hole locations determined, I used a freshly sharpened gasket hole cutter to make the perforations. The process worked out fairly well.
Paul
