First, do you have the PHS report? If not, then get one on your car. That will tell you everything you need to know to have one reproduced and I recommend AG Backeast to make the tag. There is rather limited info on those tags that year, even more so on a 68. In any event you can have a tag made to replace it but you first must spend the 50 bucks and get your PHS report for your car. Good luck.
how do you do that without the body tag? I though that was the info you used to get your PHS?