If the original tag doesn't exist you've got the best choice of what to put on a fake tag in your signature line as a tribute to your dad and his car.

Miss ya Dad
3-31-55
9-21-10
70 Coronet R/T Convertible


Trying to recreate one from "air" isn't about the car or documenting the car, it's about the resale value of the car.

Enjoy the car, treasure the memories of your dad and quit worrying about the fender tag.

If you actually have the original fender tag, post pics of it no matter how rough it looks.
The experts on here will have no problem helping you document the car.

They're not gonna help you create a bogus tag because the original is long gone.