i built mine out on the 64 like the one @Beams did. it started as a /6 car and the BnT was straight clapped, and at the time those were difficult to find, the rebuild was expensive and the shaft was an unknown player in the game. i also wanted the ability to repair it easily and economically should something happen.
part of the consideration should be can you the rear yoke on the drive shaft with the rear end you're installing? because if you can't, basically you'll be building a new shaft anyway.
anayway, if i were in the same situation more than likely i'd go that route again rather than swapping out the tail shaft & housing.