The extra 3" in rim width puts you 1.5" out further, and the backspace will add some to that. So measure 2.5" from where your tires are now and you'll quickly realize how far out it will be. I'd go no wider than 16x8 with that tire size, and no more than 4" backspace if I were you. 285/75 would work with a 10" wide rim.