When you get over 8 inch wide on the rear you really need to pay attention to the backspace and test fit/measure the clearance BEFORE mounting tires on the rims. I have 17x9's on the back with no clearance issues. the rims are 5.5" BS. Not all cars are exact. When I mounted mine I had to loosen all the body mount bolts and shift the body to one side to even out the space on each side. I was intending to go to a 17x10" rim, but they were not available in the rims I bought. I'm actually glad I didn't. They probably wouldn't have rubbed, but why bother if I didn't need to?
Tom
Tom