What’s the exact process to identify a real 66 Formula S Barracuda?

Correct about the emblem, it also is not flat like the 66-up ones, has the very slightest curve to it.

As for the Goodyear Blue Streak tires, they came standard on 65-66 Formula S cars and also non-S cars that had the heavy duty suspension with the 5.5” wide rims....no code on the fender tag for the B.S. tires

Here is my dads car

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Yep - just wounder about the tires - I have half of my build sheet on the silver one.