Abstracted
Slop some paint on. Let it dry. Polish off all the stuff that went outside the lines. The stuff in the grooves will remain behind.
The paint has to be something that will easily polish away without damaging the finish. This will take some testing in an inconspicuous spot.
I’m thinking nail polish might work well. Variety of small paint sizes available, cheap, gloss finish, and can be removed with acetone. May even be able to use a rag very slightly dampened with acetone to polish the stuff off on the surface. A sharpie marker is my backup idea.
(I’m assuming the plates are plain stainless steel. If they have a clear coat, this is a very bad idea.)
