Mike,
The differences in the Stones that were on that car bumper and the stones we see today have always been noticeable, especially when you zoom them up as far as possible. Once I received the high definition photos from the Mining and Mineral Museum (Steve Decker), I started really going over every inch of the stones.
Those pictures can be blown up 400%. Pretty much see the nose hairs on the priest.
The copy of the original 8 X 10 photo on the bumper, which I received from Dr. Glover, can also be zoomed quite a bit to bring out more details.
Not saying this is what happened with the Stone Maps, but I have noticed that whenever questionable artifacts have turned up, the originals, more often than not, disappear leaving nothing but photos, photocopies and reproductions to be examined. Things like the Latin Heart, the Bilbrey Stone Crosses, the Calalus artifacts.....etc, and almost every treasure map that ever existed.
Can't help but notice the pattern.......
Take care,
Joe