Hi to all! You need to use an enamel (for plastic) model paint available at any hobby store.... You can blend color to taste, fill in the print, let it set a bit, and lightly clean up, wipe away residual, with acetone... If you screw up, soak with acetone, whip away, and try again.... Now, here is the trick!!!!! Let it set for about 6 months! it will age harden, and is almost impervious to any solvent, as in, you almost can't remove it without heat or some other extreme solvents.... That's it... go get'em!! Best to all, til....lat'r.....GT........