Searched high and low to get this figured out as I am sure many have. Here is what we installed on our DJ:
Front 20x9 (+35mm offset) 255/45 20
Rear 20x10 (+50 offest with a 6mm spacer) 285/40 20
We had to use a 6MM spacer to get the clearance in the rear. It does not rub UNLESS you are getting a lot of articulation out of the suspension (pulling in sideways on a steep driveway - the angle of my driveway in the pic is not enough to do it).
We found these wheels for sale in the local classifieds off a 2008 Jeep SRT 8.