Started removing the window glass today, beginning with the rear window, and then the side windows. The rubber molding was dry-rotted so it was fairly easy break apart with fingers and careful use of a screwdriver. The glass came out easily; I’m surprised at how thin it is, it seems like my 1970 Beetle rear window was much thicker.
The rear windows and side windows are all marked as made by Sekurit. Don’t know if there’s a way to tell if it’s original glass or not. I’ve been looking for an original front windshield since mine is badly-cracked, but after reading several posts on TheSamba.com about original glass being fragile, I think I need to research it a little more and make sure I choose the safer windshield (if not the rest of the windows glass). Laminated vs. tempered vs. original vs. new.
Once I removed the side windows and rear window, I was glad to see that the rust spots around the windows rims were not bad, or at least they weren’t as bad as I thought they would be. I was afraid I would be welding-in patches or lead-soldering some sections. The windshield damage remains to be seen.

In addition to removing some glass, I also began treating some rusty fasteners with Kroil penetrant to aid in their removal later.

Total time: approximately 40 minutes. Photos follow.