I assume you are talking about the 3 suspension lift kits available for your truck.
4x4partsCalminiRancho.
I believe these 3 are your so called "articulating" suspension lifts because they keep the arms in the same mounts, but push arms down to give lift.
I leave out the Trailmaster kit because it is a drop down kit and doesn't really change the geometry of the front suspension.
With the 3 kits I mentioned, the lift is obtained my simply cranking the torsion bars. The new upper control arms are only to allow for correct alignment after you crank...and to allow for an extra 1-1.5" of crank to be done without the upper control arms hitting the upper bump stop.
On all 3 of these kits, you get a SLIGHT gain in down travel, but you gain no up travel at all.
To be completely honest with you....you can crank your t-bars up with the stock upper control arms for 1.75" of lift......and MAYBE 2" of lift if you get the low profile bump stops from 4x4parts.com.
If you do want to get the suspension lift upper control arms you DO NOT need to get new shock, new t-bars or extended brake lines in the front. You can use the new upper control arms with the supplied ball joints, crank the stock t-bars up (may need to re-index them). The stock shocks have plenty of travel and will still be in their working range.
My theory is, why replace things you don't need to until they are in need of replacing.
NOW, since you said you are into the more fast off-roading I have a great modification for you. The stock from struts, are REALLY SMALL....and they heat up and loose their dampening abilities very fast over rough terrain. What I did was cut the top strut mount off, weld in a shock hoop on top of the frame and put on a full length shock. UNBELIEVABLE how much more smooth the IFS was over the whoopty doos and high speed straights....
you can kinda see the top of my full length in this picture....if you want a better picture let me know.
http://pic50.picturetrail.com/...1.jpg