dash plate restore

my C-120 dash plate all the white or most of it is gone off the lettering. I seen somewhere where a guy showed how to restore them back to new condition. can't seem to figure out where I seen it now. was going to take white paint marker and real careful color the white back on the plate any ideas?

We do them on every tractor, there's tons of pics around here somewhere lol. We clean + prep the panels, then use a plastic primer and black paint on them, then do the letters with an oil based paint marker.