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

4mulaSvaliant said

If you want to take a measurement of the depression in the body. I can let you know.

Click to expand...

Just measured the opening in my 65 Barracuda - it's right at 3 & 1/2 to 3 & 9/16 inches. Confirmed the same measurements in my 65 Signet convert. Hope this helps.