the gasket listed in the parts book for the second gen trucks is just a roll of adhesive rubber to stick to the inner edge of the glass. i ordered a roll for my truck before taking it in to a glass shop for the new windshield and the guy said its purpose was to keep the new urethane windshield adhesive from pushing out during install but he said it was unnecessary and he installed it without it and it turned out pretty nice. although when i repaint my truck and find a good oem windshield to install ill probably have him use it. ever since then all the trucks at the junk yard i've seen with aftermarket glass appear to just have the urethane adhesive on them but no gasket on them. i can get you some pictures to show you what i mean if you want but its main purpose is mainly cosmetic and doesn't really "seal" anything, thats the job of the urethane adhesive. first gen trucks are a whole different story since they have a rubber seal that is "roped" in like our second gen's rear window.