Something that is very time consuming is to write on the metal sheet.

using the can transformer it's pretty easy, just draw text in a CAD tool, convert to gcode and run it through the transformer:

this application was one of the reasons I made the transformer. I wanted to label some shelves that were outdoors and I thought that cut up cans would make a good weather resistant material to make the labels out of. Cutting cans up was relatively easy, if a bit painful when I got poked by a sharp corner. I then used some number and letter punches to stamp IDs on the labels. That was tedious and the stamped IDs didn't turn out as legible as I'd have hoped, due to the size of the text and the lack of contrast between the stamped letters and the background. Using holes like this has no such problems.