Alright so here is the quick run down of these kits. I may over-explain some concepts so that the future forum browser may find some useful info.
In alignment, Toe is a deviation of your wheel from left to right in a typical turning fashion. Camber is a deviation of your wheel's vertical straightness (top of the wheel tilted towards or away from the wheel well). Caster is a deviation your knuckle's rotation about the center of the wheel/axle. Caster is the least important and relevant to our applications. Our discussion focuses on camber.
Your front upper control arms mount to the frame of the vehicle by two downward facing studs passing through an elongated hole each. This elongation can best be described as widest left to right. This means that if you were to have the control arm detached from the knuckle and loosely fitted into those two elongated holes, you would be able to slightly shimmy it towards and away from you if you were to face the side of the wheel well. This means the holes are not very wide. Maybe an inch or less of play. Thus we can conclude that if the control arm is shimmied towards the wheel well, the top of the wheel would tilt inward as well, and vice versa.
Out of the factory, Ford new exactly the right position for these control arms studs to be located in the elongated hole for perfect camber alignment. So they included a locking shim with each hole that restricts the placement of the stud within that elongation. Each shim is basically a washer with a hole the exact size of the control arm stud that uses two tabs to lock it's location and restrict the stud placement to just the right spot. Without these locking shims, the studs could potentially 'lose their place' in the elongation and need alignment constantly.
When our suspension geometry changes and we need to be able to adjust the position of those studs in the elongation for correct camber, we're given two options.
The cheapest is to buy some heavy duty regular washers and replace them with the locking washers. They will give the studs their bearing surface on the frame for loads but will no longer restrict the stud position. This is a cheap option, but it's disadvantages are twofold- first, the fact that the washers do not lock means that it is possible for the alignment to get thrown out of whack more easily with the right jolt to the suspension. (The only thing keeping those studs in their spot would be the clamping action of the nut on the stud). This means more potential alignments. The second is that it makes it more effortful to make more precise and gradual adjustments in the shop, since the position of those studs will rely on a technician pushing and pulling to get them in the right spot (essentially).
The second option is to buy a camber adjustment kit such as Moog offers. While more expensive, the kits give you the chance to have a washer-mechanism that provides accurate adjustment with a wrench (via a hex nut) and the ability to lock that adjustment in so it doesn't get out of whack. I'll spare you my attempt to explain how it works. All I can tell you is that it looks like some impossible contraption until you have it in your hand. Then it makes brilliant sense as you install it quick as as flash while laughing at how simple it really is. I even was lazy and installed them without disconnecting any of the suspension or ball joints
The price? A bit much to be honest. But the craft is top notch in my opinion. Each wheel kit is sold separately, meaning one front wheel had two adjusters - one for each stud. The backs follow the same principle, except there is one adjuster per wheel. Doing those will make sense once you've seen and done the fronts. I moved quick and did all four corners in about an hour tops.
I have a lifetime alignment package with Firestone (I actually have a good one by my house a stone's throw away) and have coil spacers and BTF control arms. The extra changes in my geometry led me to believe that it was a good investment and I still am happy I made the move to invest in them. I have the piece of mind of knowing I have rock solid alignment that can be tweaked as necessary anytime. My understanding is that these trucks will NOT be within alignment spec if you have coil spacers without removing the locking shims. The camber simply won't be right.
Hope this wasn't too long winded or hard to stay awake reading. I wanted to get it all out there as a reference to others later on.
Standing by to answer any more questions.
-Dubya