63-66 Dart. How wide of a tire on the back?

66 Dartman said
I got a 15"x8" 275 r 60's moved my springs in 3/4".

I love to see more of that 66 rear end/tire combo......it's that a 8.75 rear? Did you cut it? Iam guessin you r using mini tubs for that 275 tire...thanks