Ok, I have removed my glass for the new headliner install. Ended up breaking the front windsheild getting it out but it had a crack in it already. So the front uses no gasket but the back does. Any reason I can not use the same stuff they use on the windsheild for the back glass? What is the thickness of the material they use for the front glass (they list 2 diffrent sizes ).Also is the front winsheild the same as a 1969 mustang coupe?