Tire Size help

Relocation kit? Just the 1/2" inboard kit, or moved under the frame rails?
I've got 255-50x17s on the rear of my 55 chevy. 27"tall, 8 1/2" rim, 4.5 bs, definitely not a rubber band look. With the right wheel bs for your rearend width, should fit fairly easily. 275s MIGHT fit too.

One important question (I'm assuming I know the answer). Do you still have the 5 on 4 pattern?

Edit: nevermind, just saw a rear disc kit, so 5 on 4.5 for sure.