Are 1965 Formula S brakes the same as 1965 Signet convert 273 2 barrel brakes?

Most of the 65's have had a 8 3/4 changed into them. I have a 65 Valiant Original Commando Convertible with auto car and it has the 7 1/4. I have a 66 Valiant Commando HT and it has the 7 1/4. I have a 65 Valiant 4 door, factory 273, 4 speed car and it has the 7 1/4. And a 65 Barracuda 273 auto and it came with a 7 1/4.
So chances are that yours was built with a 7 1/4. They were not known for their longevity. I had a built 318 in my first 65 Barracuda and put a 8 3/4 in it when you could find a complete one for $100. After 7 yeas I decided to sell it and pulled the 8 3/4 and put a 7 1/4 back in it. It lasted 2 weeks before I had to put the 8 3/4 back in it. The spider gears were in small pieces in the bottom of the casing.