The computer and books may not go back beyond the three numbers and three letters series and would probably show anything not having a number followed by three letters as a comercial plate, but that's just a guess.
I media blasted and straightend mine, painted the background and the back and tried to roll paint on, as was done originally. After cleaning up the mess, I tried to hand paint the letters. After cleaning up the mess again, I tried to tape the letters and paint them. After cleaning up the mess once again, I took it to a sign painter and was pleased with the results and had no mess to clean up.
