Mark,
I found a guy who can emboss plates.
I have purchased a door-jamb data plate blank from a supplier after rejecting same from another supplier. Both were to be engraved rather than embossed, but in my search for more accuracy searched an found an embosser. He can emboss both 1/8" and 1/4" letters/numbers; the latter might be perfect for the fender data plate.
Do you have the exact data you want embossed? I have the basic dimensions and layout here on my car. I'll see if it can be duplicated.