Ask and you shall recieve! (Flip Top Gas cap Adapter)

BILL!!!!!!!!!!! You nailed it! Your above comment rang a bell!
That was exactly the situation! My 69 is also on the inside of the quarter. Not the outside. It seems that NOT ALL of the later model cars are installed like that either.
I am also thinking in the case of my friends Duster, that there was yet another ring/spacer/retainer of some sort that also held his off a bit. He did have a fix for it, and managed to mount his just fine but Im not seeing an easy solution to this really. Not with the current product as it is... anyhow.