Dually tire question.

I have a 2014 F350 DRW. I probably have about 16,000 miles on original BFG. I was thinking about rotation the tires, and while looking real close I noticed both out side duels were way down compared to the inside dual. I know I must rotate, but want to slow up this excess ware. I figure I probably need to lower the tire pressure on the out side dull. Just wondered what some of you are doing to keep the wear even. I run tire pressure at Ford's recommendations which is 65 on the rear.