If you can see the holes from the underside of the hood, there may be body filler in them. If you can locate them, use a very small drill (1/64") in those areas....if that is in fact the holes that are filled the drill will easily open the holes up. The drill, if turned just using your thumb and forefinger, will not penetrate the metal if you are in the wrong location. I had to do this on my '66 that had the holes filled and it worked well. You'll know right away if you're in the right spot....the body filler used in the holes will start crumbling I was able to use a small round file to further open the holes back up and reinstall the original letters as they were originally with the small mounting tabs that the letters fit into. The space between the tabs on each letter is different, so having the original letters will help you determine where the holes are.
