You can use with anything from 4 to 4.75 worth of backspace. Most 15x8s I've picked up off the shelf tend to be 4.25 or 4.5. E bodies have large enough wheel wells that 275s will fit well with a 4.25 to 4.5 backspace.
The car in my avatar was photographed with 15x8 all around, 4.75 back space, with a 235/60 front and 295/50 rear. Everything fit tight, but they all cleared. I've since converted to 15x8 front with 4.5 backspace and a 26x10 tire and 15x10 rear, 5 backspace and a 26x12 tire. Rear leafs had to be moved in 1" and the front fender lip needed rolled and the vibration brace cut out, but they all still clear.
