Put it together and drive it. If you have driveline vibrations, get yourself an angle finder and measure your driveshaft angle. If you are NOT running a CV driveshaft, your pinion and transfer case output should be parallel. If you are running a CV driveshaft, you pinion should be pointing directly at your transfer output shaft. Degree shims come in varying sizes for you to choose from to dial it in. Another alternative is a transfer case drop, but I am not a fan of those as I cannot see giving up ground clearance you just got by installing a lift. (it's your Jeep though) Take the time to set up your angles right and your u-joints and bearings will thank you later. Half ass it now and you will be changing u-joints on a regular basis wondering why you are rebuilding your transfer case sooner than all of your buddies.
It's really not hard, but every Jeep is a little different. What works for your buddy with the same setup may not work for you.
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