Re-setting the windows will have to be a future project for me, unless I'm absolutely forced to.
I have been scraping, scraping, scraping. Under the silicone are layers of other substances. Some may be the original stuff from 1974. Scraping alternated with some stainless steel wire brushing. The wire brush removes clear coat, so you have to be very cautious. The aluminum on the roof around the antenna mount seemed to be much softer than that around the windows that I have been re-caulking. I wonder if it is because the clear coat is almost completely gone on the roof and some remains on the sides? I may eventually polish or re-coat my
Sovereign, but I don't want it looking too tacky before then.
I also tried some carburetor cleaner, Wally world brand, similar to Berryman's B12. It seems to take off the older, stickier, dark gray caulk, after you scrape off as much as you can. Since it evaporates almost immediately, you have to wipe it very quickly to get the best results. I had to spray the same area two or three times. I would scrub the first time, then wipe away the residue the subsequent times. I will probably try this some more when I get back to work at it, but remember it is very flammable.
For something less volatile I was thinking of buying some silicone remover. Lowe's had some in a large spray bottle, but I didn't know if it was any good. I may pick up some tomorrow.
I would have liked to rivet my rooftop patch in place and make a nicer looking job of it. I looked around Temple for some appropriate rivets and found nothing I thought would do. I know nearly nothing about rivets, but I'm learning. I thought the guys at Fastenal would smile, then reach behind the counter and pull out a fistful of Olympic 5/16's and send me on my way. What I did get was a puzzled look. I have to hand it to the two guys there, they Googled it and then found something comparable to Olympics from a supplier that they use. Of course I wanted them right then and said "no thank you" to the offer to order some up for me.
As for caulk, the RV place down the road only had 721-UV in white. I need to pick up a tube of Silver/Gray in case I have some larger gaps to fill later on in areas that will show. The Parbond has worked well in the size gaps that I have filled so far.
One thing I have learned from this experience and others: I won't use silicone caulk on aluminum. I'm pretty certain that this silicone was put on within the last year. It looks bad. It peels up around the edges. It leaks. Its hard to clean up.
Still wondering if I can find parts to fix my antenna-raiser.
Best of luck,
Stephen