Not many of these cars have the original frame anymore, so checking the VIN on the frame is not that accurate. It's easy to buy a junk car with a title and a good frame and move the VIN tag and frame over to a different body. It's probably not legal, but easy to do. I really don't know how picky they are nowadays about how the VIN tag is attached on a 60 year old car. A lot of these cars have dropped their VIN tags due to corrosion over the years. If it was me I'd epoxy it back on.