the nuclearlemon ran 4" skyjacker with extended shackles for years, no dc shaft required. did have to put 4degree shims in the front. i don't know anyone who required a dc shaft with the lift because the ujoint angles don't change. i loved the skyjacker springs, as did a few friends and they must've held up because i met a guy at cruise moab four or five years back (when we held it at that picky campground) that is still running the springs. i was number three to purchase the 4" skyjacker springs back in 91 or so. my buddy steve bought the first set made and my buddy lane bought the second set made.
i would not, however, run their shocks. i had they eye snap off one, and i know two others that had the eyes snap off. i did flip the rear springs for a bit more wheelbase (garners a couple inches) and a p.o. had already put a shackle reversal in. ran it with 35s for a while, but mainly 33s for better road (couldn't afford to do gears). i did have the front shaft extended a couple of inches a few years later. fenders were already cut in the rear from a p.o. bushwacker mod.
reference pics, stock with sagging springs, 2 1/2" kidney busters (rancho), 4" skyjackers, 4" skyjackers and nuclearlemon paint. 33" tires in all but stock
ige tlca #1431