I'm running about the same as you it sounds. I have a 3" lift,aftermarket wheels w more offset,and 32" Dunlop Mud Rovers.No bump stop extentions. I had a good amount of rubbing and cutting of tires in the rear wheelwells prior to getting the grinder out. I took off the plastic trim and used a grinder to trim the metal lip/flange on the inside of the wheelwell.I then re-installed the plastic trim. There isn't much clearance when fully flexed (not even 1/2 inch)on the wheelwell, but it no longer rubs.
The gas fill tube cover still gets an occasional rub here and there but doesn't show any signs of severe damage.