There is a huge, shit-filled drama thread elsewhere. I am not gonna repost it here.
The fact is, if you are using off-the-shelf parts from Kartek to build a kit with a 1" bore uniball, you're going to be using a 1" to 3/4" adapter.
You'll need to clock the uniball so that the misalignment spacers do not bind at full compression, and droop needs to be limited just before the joints bind as well. This is how your stock joints work...they can angle farther over at full compression, and the stock shock limits the droop angle. Since the uniball clocking is fixed, and the 1" to 3/4" adapter does have a limit, and droop is more readily available on stock arms than compression, the inevitable choice is to clock as much droop as possible in to the arms, meaning you must be damn sure you are running the exact same compression stops as the designer did on the test truck. You also need to ensure that the joints can never, ever bind on droop either...all the pictures of busted spindle rings on 1st-gen trucks are the result of bound suspension, either at compression or droop.
Before you run them, you need to cycle the suspension and determine if you are running a bump stop which is compatible with the compression misalignment of that 1" bore uniball and the 3/4" adapter they use. That is the "buyer beware" part of this, it is something every owner should be doing anyway, Chaos will even tell you this (if they're drug in to a shit-filled thread elsewhere)...but I do not think that long bumpstops should be an assumed part of a kit designed for additional travel, nor do I think travel should need to be limited to accommodate a major joint, particularly on compression, when the joints are clocked such that droop will bring the halfshaft in contact with the lip of the inner CV joint.
Lack of a lock nut on the long bolt through the upper control arms means that as grease is eliminated from between the arm/bushing interface through use, the poly bushings will begin to grab the arm and the large flat washers. Eventually, because the bolt is torqued to a significant amount, the arm, bushing and washer will begin to turn the nut. This wears the bolt, and introduces a sickening, extremely difficult to identify "clunk" in the front end. This isn't a Chaos problem, it's an Everyone problem who specs poly bushings in the upper control arm without providing a lock or jamb nut. The design of the lower arm doesn't allow the same thing to happen. In my experience, grease ports are a stopgap measure, and must be combined with regular maintenance...not a big deal if you're used to it, but it means loosening the bolt so the washers can move, shooting grease down the port until there's clean coming out the ends, then re-torquing. Easy job, but raise your hands if you do this. Properly done, the washers and sleeve remain fixed on the truck, and the arm and bushings rotate around the sleeve, against the washers. If the sleeve is too short, there will be too much friction between bushing and washer, leading to the problem I mentioned before. Yes, my sleeves were too short, even the replacement sleeves were too short, when I rebuilt the arms. The best solution was regular maintenance and a jamb nut...no more problems, tho the poly bushings still squeaked like the kid in that WoW video in General. I never had a problem with the uniball squeaking, ever...just corrosion, but then everything corrodes in the Midwest. Running heim joints solves the majority of the worst problems I had with the arms, living in a place that doesn't salt the shit out of their roads solves the corrosion problem...suffice to say I'm very happy to see companies offering arms which rotate on a bearing, they are far and away better than the metal-to-metal stock configuration, and don't have the awkward maintenance issues of poly bushings. When the heims start to get loose, replace them and get an alignment...MUCH easier than replacing worn poly bushings, or all the bullshit necessary to properly grease them.
This was all from my own experience on a 1st-gen Tundra. The "good things" I hear about parts with which I've had less-than-stellar experience seem to be from two camps, people who don't know any better and stay within the realm of "basically stock" trucks (most of them), and people who assume everyone else is checking everything before they run (very few, but they exist). I no longer run Chaos arms, and the arms I had were sold for cheap to a buddy along with a different company's adapter which did not exhibit the same design limitations as the off-the-shelf parts. The arms I do run now were a one-off (at the time), at my request because I was sick of the poly bushing bullshit.
Bermise asked me via PM for some advice on the heimed arms...no problem. First and foremost, before you adjust anything, make sure you pull the coil (not the entire coilover, just the coil...measure exposed thread with calipers so it's easy to put everything back together) and cycle the suspension (it's easy, use a floor jack). You're inspecting first for binding at the joint before metal-to-metal contact in compression, then to find the first joint which binds on droop. If your bump stops are long enough, and coilovers short enough, you're ready to mess with the heims.
With the heims, call and ask if the joints are pre-set on a jig to the correct length. Also ask if any threadlock was used. If the answer to both questions is yes, head to the alignment shop.
If no to the threadlock question, grab your calipers, pick a good reference on the heim joint (base of the head, OD of the cutout for the joint, basically anything but the ball or bore of the actual joint) and measure length for all four heims (they should be the same). If they're not, but they're close, pick a good number and set both rears exactly the same, do the same with both fronts, write it all down, pull them apart, throw some threadlock in there (I used blue...you want to be able to move them later), and reset everything with the jamb nuts hand-tight. Put them on the truck (attached to coil bucket and spindle) and crank down the jamb nuts. IIRC the nuts are either 1-1/8" or 1-1/4"...pick up a big spanner from Napa, as of right now, that's a necessary tool. Then head to the alignment shop.
If they're not set in a jig from the factory, post back, that's a long response but not difficult or painful, I just don't wanna type it out if you don't need it.
-Sean