It's amazing that there's more muscle cars now than there were in the 60's. (heh)
Lot's of clones out there, not always a bad deal though. Seems guys put a ton of money into them to make them look like the real deal. You can buy them cheap in most cases and enjoy them but don't think your going to make money on one in the end. No matter what happens there still clones.
I owned a real 1968 GTO (same body style) triple black convertible. 1968 was the first year for the rubber bumper and it was standard equiptment. The one I had also had the chrome bumper (very rare) the option on the order sheet was Endura delete. I liked the Endura (rubber) bumper better but I was not the original owner.
The cheaper tempest came standard with the chrome bumper with upgrade to Endura.