Roof Rust and Protective Tape
This is what my roof looked like after 20,000 miles and two years. There was rusty metal exposed in 30+ places around where the penthouse had been rubbing on the roof.
Sportsmobile West sent me some Avery UHA (Ultra High Adhesion) tape to cover the wear areas. This tape is really beefy stuff.
I sanded the rust down to bare metal, cleaned everything up with alcohol, masked and painted with tan spray paint (all the way to the penthouse fabric), and then carefully applied the tape. It was a cold day when I did this, and I found warming the tape slightly with a hair dryer was necessary to make it soften and adhere properly.
Yes, the spray paint I chose doesn't match my body color exactly, but because the seam is hidden by the tape (and by the penthouse when it's down), it didn't really matter to me. When the penthouse is down, the tape isn't very noticeable, because it's black like the top's rubber seal.
You can buy this tape from the Sportsmobile Store.