My attempt to do the rear window repair on my Roadster.
Fortunately only a small length of the glue had let loose.
After carefully spending more than 2 hours I followed these steps:

This stuff is a mess but fortunately I was wearing latex gloves
I raised the bow and first scraped all the old glue from the glass in the place where the repair was needed and made sure it was clean and dry
I placed a folded bath towel and placed it inside behind the glass to give it support against the canvas.
I then applied painters tape and masked all of the outside of the glass where the canvas top meets the glass so that all the excess glue that might squeeze out from the canvas would be on tape that I can simply remove from the glass for a quick cleanup

I first applied the

3M Single Step Primer

3M Single Step Primer

and allowed it to dry as instructed before squeezing the bead of

3M Window Weld

3M Window Weld

I finished by using some strips of gorilla tape and carefully pressed them against the glass and canvas again with the towel beneath the glass for support
I then closed the top completely and latched it.
Now I'll just let it sit overnight and tomorrow carefully remove the strips of gorilla tape and then the painters tape from the glass and see if the repair was successful