First of all, clean the cowl with some alcohol to get off any residue and/or oils.

Then apply a primer.

As for your choice of paints, that is a personal thing. I have had very poor luck with Lusterkote, although there are people who have had good luck with it.

If an enamel or lacquer IS LABELED ACRYLIC it is fuel proof.

Many people use automotive paint for painting. I don't use it because of the high cost compared to other paints.

SOME of the Rustoleum paints are fuel proof - I am not sure which ones.

I use latex paint at 25psi - 30 psi for painting. After the paint cures I clear coat it with waterbase polyurethane. Flat latex takes about 7 - 10 days to cure.

I do not paint the inside of my cowls (just what gets in from overspray ) and have not had any problems with weaping.