ORIGINAL: jester_s1
Rustoleum is hit and miss on being fuel proof, as you can see. A really popular product for topcoating latex is the Klass Kote 2 part unrethane clear. Most any automotive 2 part clear will work as well. Acrylic laquers like Lusterkote are fuel proof too, but the solvents in them can attach the latex.
Rustoleum is hit and miss on being fuel proof- very true to a point. It seems the flat colors work better IMO. I have it on 2 of my planes and the paint is still holding up after 4 years. However, the trick is we have to keep the plane clean. Make sure no glow oil residue is sitting on it, so after a day of flying, clean your planes all the way until you see no residue of any kind. That's the trick! If you leave oil on the plane, it will start eating at the paint over time.
Pete