Spohn upper/lower control arms, as long as you keep the stock ride height, they work well for the stock truck, when I 1st got my 14 after the cam swap it hopped bad enough it bent a few trailing arms, the Spohn rear arms stopped it, but then I lowered it and that opened up a can of worms.
I've broken a few passenger side upper's Spohn was great about replacing them, then I found out the issue was I lowered the truck.
if you lower your truck, you'll need
Control Arm Relocation Brackets
to correct the rear axle geometry, a 4 inch drop pulls the rear axle forward about 1/4- 3/8 of an inch. if you do lower it, the Spohn adjustable track arm helps keep the rear centered after lowering.
,after the rear brackets were installed no more breakage, this winter I'm going to pull all of it out and make my own bars to correct the issue with out brackets.
As for gears with the 8speed trans it's a waste of money, unless you want to go from low 3s to a 3.92, anything deeper than 3.92 is unnecessary.
, Not bad for a 392Ci NA 4400 lbs truck ,