A GTO in the ten digit range? Blimey!
Let's see; $10,000,000 - ten million dollars. Eight digits, and not far off the world record GTO price. Ten digits makes for a car worth well over one billion dollars.
In addition to which, the fact that you were able to pull up next to one means it was almost certainly a fake - re-bodied 250 GTE or glassfibre datsun-based lash-up, it matters not a jot.
Can anyone beat that? Almost certainly.
However, if you really saw a real GTO, and a real Shelby - so many replicas - then you win the thread. Bravo!