The most work involved for the Gen 1 TC Kit is involving shock hoop installation and getting the stock UCA's removed. We cut everything for the UCA and cleaned up the stock mounts and sleeves in a lathe. Doesn't sound like much but you will save time if you get stock UCA's ahead of time to prepare these parts.
Shock hoops were difficult for me since my Bilstein 9100's are about 19.75 inches compressed (comparable Fox/King's are 15). I used the TC Hoop kit with a small DOM sleeve on the front of the hoop, I also had to clear more sheet metal and fabricate an upper crossmember. The TC Hoop was intended to triangulate to the engine mounts not using an upper crossmember, engine mount braces interfeared with my higher shock placement. If you're proficcent at welding this will be easy, the bulk of the work is cutting/notching & burning. It took 2 of us about 72 hours each to turn around the install in one weekend.
I got the first gen kit to retain ball joints for better streetability. However since then I've waffled to prefer the uniballs. I haven't broken a BJ yet but the replacement cost is comparable if you source the spherical bearing's right. Lots of fab companies sell FK replacements at a steep markup. Also the torsion bars are a PITA for maintenance, all of my t-bar hardware is new but it's still a pain to service. Not really any tunability in my eyes, I'm either at the ride height I want or I'm not. It's a lot easier to remove two bolts & hose clamps if you want to cycle the arms.
My latest observation of the first gen kit is interesting. I've compared lots of pictures of first gen lower controll arms versus second gen LCA's. There are distinct diffrences in the construction of the arm's front tube and the shock tab locations. Early production first gen's locate the shock tabs behind the front tube completely on the LCA's upper plate. Also the front tube's bend is around 17 degrees.
Second gen LCA's have the tabs located as far forward as possible with about a 30 degree bend in the LCA front tube (plus the second tab set).
Now here's the interesting part

. My LCA's match the geometry of the second gen LCA minus the rear tabs. I speculate that through the course of manufacturing TC found that one LCA could be manufactured for either kit minus the rear tabs. Their web site says the first gen kit can support coilovers if you remove 4wd due to the axle shaft interferance. A friend measured the outter diameter of his coilovers, about 4.5 inches with distortion from being compressed. Based off of this there is about a quarter inch of clearance at the axle shaft. Second gen kits appear to have this tight clearance as well. A second gen truck parked next to me once but I didn't get to take a look up close. Turning misaligned the axle shaft slightly but not enough to interfear. The torsion UCA clears a 4.5 inch coilover easily. TC can offer individual kit replacement parts so eventually I can get second gen UCA's w/ uniballs.
Also notice the rust

. Bilstein 9100 shock bodies have a nickel plated finish that requires maintenance, basically cleaning and oiling the metal. The instructions were very specific about this. Since this pic I have cleaned the shock bodies with Scotchbrite pads. I'm oiling them with Remmington gun oil, I like the spray cans and throw on a coat every wash. The TC steering sleeves require the same treatment but everything else is painted plus a clear coat.
I'm ordering Bilstein coilovers in the next three weeks (unless I burn my money moving out of the slums

). My 9100's will move to the back of the arm. Also my shock hoops and upper crossmember will be bolstered to support the weight of the vehicle.
I sell shoes to fat chicks in Ethiopia but I take the hydrofoil to Arizona on the weekends

. This setup is awesome for Arizona roads, especially the northland where trails are peppered with volcanic rocks. My wheeling mileage is slightly higher since I'm cruising above city speeds when possible. I'm very pleased with this setup and the ability to upgrade individual components. My truck is a daily driver, handling characteristics have improved in all conditions on and offroad. If you're prepared for the work involved this setup will please you for DD needs and rough roads in the southwest.
Sorry, I think I've given TMI. Enjoy

.