My set up will NOT work without a wider rear with leaf offset brackets and reduced steering radius.
I'm running a square set up. 18x9.5 with 45mm offset; that's about 7.2" back spacing. The front hits the frame rail after 1.5 turns, and rubs the fender before that. One turn from center has no rubbing, and that's more than enough for all driving aside from Parking lot maneuvers.
The rear end is 60.5" wide with 1/2" offset brackets. I've gotten a little rubbing over huge bumps, but otherwise I'm good.
265/40/18 or 275/40/18 on all four. I've run both.