This can be done but you'll have to take the whole trans apart to change the output shaft because the 2wd shaft is longer than the 4wd shaft. And you'll have to get an extension housing for the c6 to mount transfercase to it.
I just did that this weekend... :chili: easy to do, you just have to gut both c6s down to the tail shaft, swap tail shaft and reassembly... For teardown this girl is awsome, I used it... :rockonhttp://www.fullsizebronco.com/forum/showthread.php?t=98095
Also remeber to swap tail shaft housing 2wd with the 4x4 extention housing...
Just to recap the 2wd tail shaft is longer then the 4x4 tail shaft, need to gut both trannies down to the tail shaft... Then swap and reassemble... and you good..
ill probly use the 460 thats bolted to it now, but if i have to find a 4wd tranny just to use its parts, i might as well just use the 4wd tranny i find, unless it doesnt bolt up
another question would any t-case bolt up to any tranny extension i get for the tranny?