Post # 36 I printed it and was waiting til I actually got the bike running again before I messed with the sidebags. Plastic Enduro's that someone jigsawed an inside corner out of. I've never done any fiberglass work, didn't even know how to buy it. So I read the detailed instructions and gave it a try....unfortunately I was using Bondo gel resin, and it's boucoup thick. It did manage to plug the hole from the inside, but on the outside (which luckily won't show when it's mounted) I still ended up with a thick mess that I couldn't really smooth when 'wet', so I sanded it and went to Home Depot to buy the 3M version, which went on much more like your description.
Here's a pix of the rough dried fiberglass before any sanding or painting. (assuming I did the picture link properly). The green color is from the bondo resin, I can't see using that again.
The main point is that I really do appreciate the great advice available on this site, For almost any topic! Thanks!