Spc I replaced the poly bushings with their new style, that eliminated the squealing and greasing problems, after I replaced the defective ball joints.
The aux tank a better call, especially if you have a tire carrier. MY fuel sender went out...It switches the pump, but fuel level not working ; I have had it for 5? years, no skid plate. No marks on it, but I don't wheel like I used to.
I use the rear locker rarely, The rear axle articlulation is pretty good with johnny-joint links (metal tech). I also do not rock crawl like I used to .
I replaced my hoses with braided steel hose kit from Slee, with fluid flush, and had a noticeable improvement. Before, many times I would pump brakes before hard braking.
Forget factory clamps. Use the worm drive smooth edge people are talking about. Carefully tighten the clamps, not to over tighten and cause boot to rip. The hardest part of the job is to get the axle out of the truck.
Regarding breather, I removed mine and run new hose up near the gas filler neck and placed a small engine fuel filter on the end to keep out dust. Axle seal leak disappeared. It was due to running hard after a super cold weather start.