Rustoleum primary colors are fuel proof up to about 20% nitro. The primarys are like gloss and flat black, Sunrise Red, Golden(?) yellow, etc. I think these are their "Hardhat" colors. The pastels and metallics are most definitely NOT fuel proof. Clear is also NOT fuelproof.

Like you I also found out that water-based poly is not fuelproof, and unfortunately nothing seems to take it off but sandpaper! Fuel makes it sticky and a little rubbery but it still doesn't come off.

On the other hand, Nelson Hobby's water-based epoxy is very fuel proof when the cross-linker is used. I've spilled 30% Heli fuel on my pattern ship's fuse that's painted with it and left it for a while with no ill effects.