It seems that you and I are standing on the same stretch of washed out back road and wanting for a nice off road tire, or at least we have run into the same problem wanting to mount a wider width tire. If I had an SXT, I would be more willing to experiment to find a solution. But with all the painted plastics on the R/T, I am unwilling to start cutting.
For the front wheels, the plastics forward of the wheels would be easy to trim. The plastics behind the front wheels cover a drain in the body floor, at least they did on the Liberty, and once you remove them, it exposes this drain to water intrusion. Removing the inner plastic fender well will allow you to see all of this and allow for discovery of just how little support you would have for the outside fender after the inner one is removed. I am afraid it may just flop around and have no support.
You might could find a way to use steel and fabricate some inner support rods if you were willing to have some exposed bolts on the outside of your fenders. What I am thinking of would be like outstretched fingers on the inside of the outter fender and bolted through from the outside and a nut on the inside. If you did it right it could look kind of cool.
Best thing I can recommend is to remove an inner fender and see what you are up against.
For the rear tires, you can't remove much back there before you run into steel of the body and the rear door.
However, I believe a 2" lift would clear most everything for the rear.
I refer you to these posts about tire sizes.
and this one where I have been discussing all terrain tires.
Good luck, I am interested in your outcome. Please post what you find.