Two things: The brush size is critical. Go to hobby or artist supply house and get the smallest tipped brush possible; or trim the brush you want to use with straight edge razor blade. Second - the sheen of the paint you use is critical; I'm guessing dead flat (dull) is required but there is also flat, low lustre, satin and other words to describe sheen. Enamel paint is very thick. Thin it with the right solvent based on the mfrs. rec. to make your job at least a 50/50 shot at success. You obviously don't need much paint nor do you need to thin the whole bottle or can, just a few drops in a glass or plastic container. Hobby supply houses have a seven inch palette with 8-10 compartments in which to mix paint and solvent. Oil base only is compatible I believe.