I'm wanting to get some 15"x8" rims so I can run a bigger tire. I currently have the factory 15x6(?). I'm not looking to spend a ton, so I'm looking at cragar soft 8's or equivalent. What backspacing works? Also, what tire diameter can I fit on them withough rubbing on frame or fender? Suggestions, please. Pictures are always nice... I'm a little lost on tires and rims.