Windsheild / Rear Window replacement

[Pyrotechnic]

Is anyone familiar with the method on PROPERLY replacing a windshield or rear window in one of these trucks ? A glass shop that I had do the windshield previously reused an old gasket that should have been replaced, and to top it off the gasket leaked and made noises as I went over bumps.

I have brand new front and rear window gaskets. It's come time to have them put in but the glass shops around here have left me a little scared, so I'd like to know what the proper procedure is. Another thing I wasn't sure of is if the gaskets go in dry or is some kind of sealant is required. Is it really that hard of a job ?