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

This car had EVERY standard Formula S item, but was not a Formula S. Also had a four speed and disc brakes. Yes, it was/is valuable. I changed the color, however (back in the 1980s).View attachment 1715784751 View attachment 1715784752


That is a beautiful car!! I love the A body Barracudas, but the 66 is my kryptonite.