About lifting boxes, We used 4 guys, plus the spanner man to lift into place my pootrol box. Sure it had the transfer case as well, but we took the doors off, put a 2" bar thru the cab, with a chain thru the gearstick hole.
Then a jack holding the weight,with two guys pushing it into place underneath the car, with another putting in the bolts.
Two guys were lifting the box from the top with the pole thru the doors. Massive job, and never again.

Yeah changing a datto gearbox is simple.