I've posted this before, but it's still relevent.
I used to run 32 x 11.5's muddies with a 2" OME lift on my '97 TJ*
Tires were mounted on stock 15x8 rims with 5.5" backspacing.
Had some rubbing on the front control arms and anti-sway bar at full lock which was easily fixed with a couple of washers on the steering stops.
Things were really tight in the rear but never had any rubbing issues. Perhaps I'm not hardcore enough or just lucky. Could also be due to variances between tire manufacturers but although I never had a problem, it was always on my mind and would have been more comfortable with a bit more room back there. ie different BS rims or spacers.
Checked the speedo with a GPS and saw no difference, but again, I guess results will vary with different brands of tires, with them all being slightly different.
Also, the stock flares JUST covered the tires with the stock rims (5.5" BS).
Had to remove the rubber bumps on the tailgate to mount the spare and raise the third brake light.
Actually the spare was mounted on a stock 15x7 rim (5.5" BS).
I was running stock diff ratios (3.07). The 3 speed auto is a bit more forgiving than other transmissions with that combination.
One other thing to consider is 32" tires are far less common, so that could be a problem if you need one in a hurry. I sometimes used to carry 2 spares (one in the tub) if I was heading too far from civilisation.
* Now added a 1"BL and 33's