Coloring Proofs

Use a white putty (paint) stick available at paint and hardware stores. They are available in lots of colors and are used to fill nail holes in wood trim. Remove oil from the marks with laquer or acetone or? then just rub the paint stick over the markings. Wipe the area with rag and mineral spirits to remove excess paint from the area. The white will remain in the depressions of markings. Wipe area with oil rag. Also works to white in missing safety marking.