Butyrate Dope from the hobby shop is the lightest paint and most fuelproof. Thin it out, it goes a long way. I've heard of the Rustoleum method, but never tried it, worth an experiment. Dope with some talcum really fills the grain nicely, as long as you sand the excess off and just leave the grain filled. Best advice I can give you, the lighter the paint coating, the better. 1/2A's are small models and the lighter you make them, the better. I've even spread epoxy as thin as I could get it, sand it real smooth, then painted. But the best finish is one that is as light as you make it and still make the wood fuelproof. Glossy and shiny is not as important as lightness and fuelproof.