Get some hard maple and carve the letters in it and then use that as a
pattern for the panel. Try the job on some scrap sheetmetal first so you
get the routiine.
If you end up with some roughness in the face of the letters, you can always
bondo that flat without any problems as it will be thin.
Good luck!

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Why isn't there an Ozone Hole at the NORTH Pole?