I just got about 9 years out of a Center Force II in my CJ-7 with a 401 and 35's on it with very good results. Last year I stepped up to 42's and the last couple runs have smoked the clutch a few times. The smoking started after I needed to do a 4th gear assault on a few hills that required much tire speed. I basically needed to dump the clutch in 4th to start out. I plan to continue using 4th gear when needed so I want a clutch that can handle it. I pulled the old one out and the lining is still good and the surfaces aren't any to glazed over either. I had a 10.5" and it looks like an 11" will fit and there are bolt holes for it.
Basic set up is 350 HP (or so) 401, NP-435, Atlas II 4.3 and 4.10 gears=118 crawl ratio. 4th gear low side is about the same as granny (6.69) in the high side. Rig probably weighs about 4,800 lbs.

A. Should I get a new CF II in 11"?
B. Buy a CF Dual Friction in 11"?
C. Buy a different brand in 11" to save some dough?
Note: No, I'm not getting an auto!

Anybody else have 42's or bigger with a clutch that holds?

For big tires, like you have, and running higher RPM's, like you might, the Dual Friction will hold better, than the CF2. Might as well try it out, to see how it performs. Might have more clutch pedal pressure than the CF2 though.