Are the suspensions on the non XR 392 and the XR392 the same?
I don’t have the XR package on my 392, but I did try 37x12.50s on stock wheels and no lift. I did use 1.75inch spidertraxx wheel spacers. I put the spacers on before the tires.
From my experience and assuming the suspensions are the same, you can safely run 37s on the road with setup I described above. With sway bars disconnected (photos 1 and 2) the front has plenty of clearance, however at full stuff the rear does make contact with the rear inner fender. Once taken off road (photo 3), the tire will make contact and the knobs will pull the inner fender liner out. When this occurred on a very mild trail, my 3 year old son asked why the Jeep kept farting.
My solution was to add Fishbone Offroad 3/4 inch spring spacers in the front and rear. I also added Teraflex Performance Bumpstops and 2 inches of bumpstop from Metalcloak in the rear only. I have tested this Offroad since then and everything has cleared. Completed badge trails 26 and 16 at Windrock and hit some other local spots with no clearance issues at all.
On the road this setup has worked great. I drove from southeast TN to Sarasota FL and back in 48 hours and it handled fine the entire way - just drank a lot of fuel!