I have to confirm the width to be totally honest. There is a chance they are 15x8.
As for the backspace I measured them when I got them but don't recall now I can't remember if the additional metal was added to the back but the center sections of the wheels are definitely moved back. Backspacing is going to be 4" - 4.5", they fit with the tires no problem.
They are off the car right now and in the front of the garage, I should be able to get exact measurements when I get home later tonight. I will post everything here.