I have 200 storage units (all full), no garage or trees. 500' x 500' lot. No place to get cover or shade.
I'm going to repaint the helm bubble before putting the aluminum and hardtop back on. Any other topside work I do won't require removing the hardtop. I will reinstall the hardtop per your experience.
The aluminum is being primed with AwlGrip Wash Primer. It's a chromate-free product that will etch the aluminum and create a strong chemical bond. I was able to hand sand the pitting smooth. The blasting created a nice mechanical profile for the primer to stick to. I'll top with AwlGrip 545 primer, light sand and more primer to get a smooth surface before paint.
Stamoid is good stuff. It can't be that bad. Costa uses it on all the new Vikings as do most custom builders. They use it because its easier to build an "engineered" enclosure. They have tools to slit fabric and can heat bond some seams. They still do sew for a traditional look. Also using lifetime threads. Just be sure to keep any bleach products off it or it will yellow.
With my Sailrite sewing machine I have done a few repairs for friends. Replacing vinyl glass or polycarbonate, re-stitching sun damaged polyester, mods, etc. Base material is deteriorated too and tears. At some point it's easier to just make a new panel. Repair work on a old enclosure is like working on a house. You have to do the demolition and then the repair. Double work.