Testing has gone well. I went back & read a lot of posts where people had problems installing a new GM seal & the glass wouldn't close all the way. It seems the NOS seals are like that we already have a better finished bottom. This will let it adhere a lot better. I'm working on seeing if we can get it a little more glass friendly then stock. you can always put wax or another substance to make it slide in easier, Just hoping to make a better seal that this does not have to be done with.