run a search and you should have plenty of results on this topic. There are plenty of threads of people wanting to put large, wide wheels on fox's. I just put some (supposedly) 15x10's w/ 6.5 backspacing on mine today w/ some 275/50/15 bfg's and they fit w/o flipping or removing quad shocks and no spacers, but a lot have to either remove the quads or use a spacer. The 17's w/ 285/40's should be around 26". 90+ had wider fenders. You might have to roll your fender lips and use a spacer. Each car is different when it comes down to it.