I made a piece of transparant plexiglass to size and after that I put 5mm sticky letters to it. I put the legend on a piece of sticky tape so the paint cannot get underneath it. I then taped that tape to a piece of A4 paper so I can turn the legend to spraypaint it from all sides.
After spraying the legend mat black from all sides I put some pieces of MDF on both sides and put a container over it zo nothing can fall on the still wet paint. This paint is dust dry after 15 minutes and completely dry after 16 hours.
After a little over an hour the paint has dried enough to remove the lettering. I again used my scalpel to do this. In the mean time the legend was held in place with the non stick sheet that was supplied with the sticky lettering. After removing all the lettering I also used this sheet to press the paint firmly against the plexiglass. This gives a better result after the paint has dried.