I don't know if you could frankenstein a CV together or not. Somehow I doubt Superturbo64 (I think that's his name on CF) went to that much trouble.
Unfortunately, this only raises more questions for me. The general consensus seems to be that the Titan diff housing is slightly wider than the R180, which means that V8 Pathy has to be running even shorter CVs than the Fronty/Xterra to keep the same track width. Wouldn't shorter CV shafts equal less "safe" front wheel travel. Maybe not an issue on a street queen Pathy, but nothing I would want on my rig.
And finally, there have only been a couple of Titan diff swaps but they have both been done with drop down bracket kits. Nobody has yet to determine if the Titan diff will fit in there without the lift brackets. I remember that there was a guy over at CF who took some pretty good measurements. He indicated that the Titan diff center sections actually sat a hair more to the center than the R180. He had concerns that the larger housing would contact the oil pan (a problem that would be negated by dropping it down 5-6 inches).
To be honest, I think this is the only way (short of SAS, of course) that the Xterra/Frontier guys will ever be able to run different ring & pinion gearsets. And sadly enough, it's only going to be an option for the M226 guys. I just don't see anybody taking the time to proto the C200 or R180 anytime soon. I know Superior has told me that they would like to, but they're not actively pursuing it either.
Obviously there is substantial cost to this, and I'm not convinced that I want that wider track width in the front.