most 4x4 transmissions with the transfer case attached have different output shafts than the regular transmission, so you would have to tear the 4x4 transmission apart and install the output shaft from a 2x4 transmission, as well as the 2x4 tail shaft and any other related parts.
at least that was the case with my experience with early [up to the mid 80's] transmissions in my junkyard ownership days.
i would say it's still the same today, or close to it.