...due to the fact you won't be lowering the diff...
this is seems to be a common misconception. Technically the drop bracket does not lower the diff . The goal of the kit is to maintain the geometry of the drive train. The brackets drop in around the diff and the LCAs connect to the new bracket. This allows a 4WD to lift the front by 6" without putting stress on the drive train.
It would be interesting measure the height of 2 diffs with similar tires and see how they measure up.
I'll have to climb under the truck to take pics and show you what I mean.
so guys how much of a PITA was the 6"?
From my perscpective 6" of lift is nice, but the stock suspension does not support it well and the 4" blocks in the back will wear on your rear leaf springs. So expect to spend a lot of extra money if you go this route to get the truck to drive nicely. For me that meant PRG UCA (for alingment and flex) extrended radflo coilovers (for handling and to remove the spacer). After 2 years my leafs were flat so I swapped the 4" blocks for Deaver 2" add-a-leaf springs and 2" blocks. My truck rides better then stock now, but it was not a cheap project.
edit here are a couple pics:
you can see from this first one that what has dropped is my lower control arm. It now mounts to a bracket that is 5" lower then it used to be, if measured from the frame of the truck. But what I think we are all more concerned with is distance from the ground, not the frame. Since the wheel mounts to the suspension in the exact same manner as before, then I would argue that the control arm is the exact same distance from the ground as it was before the lift.
This one shows that the center of this mounting bolt is about 11.5" off the ground. This should be a measurement that other folks could take. My tires are 33.27 in diameter, so if we get the same measurement and adjust for change in tire size we can put this debate to bed. My guess is that this measurement will be pretty close to 11.5" for everyone else, but I could be wrong.
BTW - If I were to start from scratch I'd seriuosly consider the Titan swap. At the time I thought that would have been a much more expensive project.