I won’t bore you with my account of the windshield “job from hell”, but I have learned a few things.
For split windshields, many center supports are sturdy enough, but very poorly attached, and doing nearly nothing to prevent the cap over the windshields from “slamming down” when you hit a hard bump. Those bumps are often responsible for either cracking a windshield or causing the windshield to “pop out”. Be there when they pull out your windshields. Reach in and grab that center support and give it a helluva tug. If it moves, FIX IT before reinstalling the windshields.
Some top caps are very flexible in the middle, due to the “gap” in the reinforcements not bridging over the middle. Crazy choice on the part of the coach manufacturer. Fix it.
If you can get to speak to REALLY knowledgeable techs at nationally known coach glass companies, do so. And be sure you get to talk to either two of them at the same company or ones at two different companies. If you talk to enough of them, you will find two diametrically opposed opinions about whether or not the gasket should be glued to the coach and allowed to set up before the windshield is installed. Make up your own mind about which method makes sense in your case. If your windshields are “popping out”, that usually means the windshields are pooching out toward the front, and they are doing it by ROLLING the gasket forward off the pinchweld (coach flange). If the gasket was glued well on the INSIDE of the flange, it would be very difficult for it to move forward.
Always do a “trial fit” of the windshield into the coach opening before installing the gasket. If the windshield does not “fit” the opening, and the edges of the windshield do not align with the flange you will have trouble if the problems are not remedied.