run both the turbo cases. they are both 23 spline inputs which are bigger and stronger. get the 23spline dual case adapter and your good to go. then you can later on upgrade to the 23 spline 4.7 gears (make sure you buy marlins total spline stuff cause its burly and bad ass) and you will be sitting pretty happy. throw in a longfield out put shaft and im almost sure you will probably never break a thing. remember, i said probably never but stuff happens.