/diy/ - Do It Yourself

First, try some organic solvents that won't hurt the metal finish. Paint thinner, mineral spirits, acetone, etc. and try to wipe the numbers off with a cloth. If a solvent works, dunk the dice in there and leave them overnight. The numbers should just wipe clean.

When they're all clean and dry, replace the color with some nice model paint or some other relatively thick paint you can dispense with a needle tip bottle into the numbers.