I had no mods on my suspension, except I did replace the shocks with ProComps to correct the bouncy ride. I considered spacers in the back to make the rear tires stick out a bit more from the wheel wells, but never got around to it before I sold the truck.
The rubbing occurred on the left side of the front swaybar. It was very light and only caused a clean spot at that point. The paint did not wear from that spot. There was also a small clean spot in the rear fender wells. I never heard any noise from that, and it only occurred when I had a heavy load on the back of the truck.
Here is a photo I found that shows the rubbing in the rear. Notice the small arc just behind the hoses.
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