Lay the window seal out in the sun and let it get good and warm. Get a length of white, nylon 1/4" rope about 1 1/2 times the circumference of the glass. Install the warm seal on the glass. Take the rope and install it in the groove where the pinch weld goes starting from the bottom in the center and going around until you come back to the bottom in the center. Leave about 12" or more hanging out where you start the rope. Take some Dawn dish washing detergent and soak the rope in the groove all the way around. Now install the glass bottom first into the pinch weld and get as much of it installed by hand as possible, leaving both ends of the rope on the inside. With someone on the outside, Start with the short end hanging out about the 12" and gently pull it out of the groove at a 90* angle to the pinch weld. This will pull the lip of the seal up and over the pinch weld as you go around. Make sure the outside person firmly pushes against the outside of the glass right where you are pulling the rope out following you as you slowly pull the rope out. It is important that they keep firm pressure against the glass right where you are pulling the rope out, or the rope will just pull out of the groove and not pull the seal over the pinch weld. Once you get it installed, rinse it off GOOD with cold water and let it dry COMPLETELY. Then take a caulking gun and run some clear silicone caulk all the way around the seal in between the outer part of the seal and the pinch weld. You'll need to stick the tip of the calk tube under the seal, between the seal and pinch weld and run it all the way around. Wipe the excess off and let it dry. Done. Never in my life have I ever had to use butyl this or that. It's just that simple.
