My 2 bits of experience.....
With That extreme of surface texture, you should have maybe "Reverse" painted the G.I. Star Logo,
(Painted a flat White "Field" first, then applied the Star "Mask", Then Painted the O.D. Green)
All is not lost.... make your "Mask",... use extra over spray protection, Shoot your Flat white from a good distance
from the "Mask" in several LIGHT COATS, MINUTES APART !! You will still get some "Fuzzy-ness", but it usually will
disappear n short time as the over spray around the "Mask" is a "Dry Paint" and will wash off.
CAPT