to use these rims and this BS wuld i need to run drag tires?

You can fit a 15x10" under there but you don't need a 10" for a 235 tire. You only need a 10" rim when you get up around a 275 (unless you are talking a low profile 17 or 18" setup.) I think the 4.5 backspace will fit if the tire doesn't bulge to much on the rim. I'm running 15x10's with 4.25 inch backspace and a 265/50/15 with a moderate bulge and I have almost 1" clearance from the leaf springs. Actually the bulge is about even with the back of the brake backing plates. My clearance problems are on the outside fender lip and thay clear there with the lip slighly rolled up inside.

this wheels would be better for that tire
http://www.summitracing.com/parts/SUM-521-5865PS/

and I think you could fit the 255/60/15 of that tire on the back with that 8" rim as well then again I'm spoiled with slightly bigger wheel wells of a Barracuda.