Looking at maybe a set of factory steel rims to mount my MT's on. Any problems with mounting 31x10.50's on a 7" rim? I will have to driving on the road to get to any wheeling events, so keep THAT in mind.
You'll be "ok" with running a 7" wide rim. The current set we have on Rebecca's XJ is a 10.5" wide tire on a 7" rim and it works fine. However we've never taken it offroad and aired down with that setup as these are just temp tires (at's) as she drives a lot back and forth to work.
The biggest issue with th 7" rim is the offset of them and the rubbing that occures, but you have that covered with the spacers.
I wouldn't run a wider tire than 10.5" on a 7" wide rim however...
Ditto on the rubbing... Feels a little limited in a sharp turn, say, pulling in/out of a parking space, etc. Also, I can tell that I am not sitting as wide. Almost feels like the XJ is shrugging its shoulders. If that makes sense... Definitely feels more comfortable the other way, but if you won't be using them all the time you will probably not mind. You will be able to tell a difference though.