OK let me first say that I do not own a CUCV so I m not familiar with where the slip joint is (on the shaft or on the transfercase). When you break the u-joint, did your shaft come apart at the slip joint (if the SJ is on the shaft) if your shaft comes apart make sure when you reassemble it you get the u-joints in phase with each other (lined up) or you will keep tearing them up.
If this is already being taken care of, disreguard and carry on.