using ctm's (or any other high psi u-joint) on untreated 4340 shafts wont last long. The ears are too malleable, and sooner or later they'll get loose and you'll have the same problem again. then again if youre dropping the cash for superior shafts and ctms, a D60 in good shape isnt much more. If you're worried about clearance, check out the Rockcrushers
http://www.mad4wd.com/tek9.asp . All the stock stuff will bolt into it. Teraflex has some high clearance centersections but they're like $1000+, but unless you plan on wheeling in Beirut anytime soon, its not worth it. Theres really no end to what you can do to the axles. If you have any sort of budget, get superior shafts and ctm's. They hold up to a lot from what i've seen, and will pay for themselves in time. If money is no object, I reccomend portalled 404's.
I do agree with you on the overbuilding. I just got some 1-ton axles. I could've easily got a 44, but i figure all the work will be worth it in the long run. Crawling around in the mud trying to fix broken crap gets old quick :roll: . The less parts you have to worry about the more fun it is
just my .03