Rustoleum "Stop Rust"
Rustoleum "painter's Touch"
Rustoleum "automotive"
I have tried about a dozen colors. 2 week cure time, soak a paper towel in Sig Champion 25% and apply to a sample. The color lightens, but doesn't transfer (or very minimal transfer with rubbing). The color returns to normal after several hours. No gumminess when rubbing. You need to let it cure though as it will transfer at 1 week.
I have not tried clear, but have a can waiting to try.
It goes on heavy though, and can become an overweight problem very quickly. My last build I used clear dope + cornstarch to fill, sanded it all off 2x, 1 coat of Rustoleum grey automotive primer, sanded well, 1 coat of Rustoleum Blue "automotive", with a couple spot touch-ups and I am struggling for balance due to tail heaviness. Looks good though, and is the lightest paint job I've done since I was young and colored dope could be had anywhere...
I also never weighed planes when I was young.
Phil