Sorry, I don't check in often enough.

After the job is done. The glass is tight to gasket, but you use a plastic stick or tool, (cr laurence has them, search plastic tool) to pry apart the gasket to glass and use a sharp angle cut on the end of the urethane tube. Push the cut nozzle under the gasket and let it go. If you heat the tube of urethane first it works much easier. Don't make it too thick or the clean up is awful. I spray the excess urethane with glass cleaner so it won't stick to anything and always use a new razor blade to remove the glue. This can be done anytime, so if you have problems with a leak the glass/gasket leak will show as a line of water coming around the glass at the bottom of the gasket near the dash usually in the corners. Hope this helps.
Jim