It seems that personalized plates, or a name lettered on the car would be appropriate.

Let's see....."Family tradition"...."The heirloom"...."Pop's Pride"...."Family Ties"...."My Inheritance"...."Hand-Me-Down"...."Family Obsession"....etc. :-)

Henry Js were most often regarded as candidates for a drag car. That would explain the big tires.

You and your dad were both lucky!