that's mot the main shaft

on the 4wd there are 4 shafts

on the 2wd there are just 3

both have input shafts
both have counter shafts
then you have the longer main shaft in the 2wd and the shorter main shaft in the 4wd
the 4th shaft is the poutput shaft which comes out of the epicyclic diff in the transfer box which is driven by the shofter main shaft int he 4wd box

from the pic you have broken the output shaft, which is an easy enough change even with the box in the car, but it's quicker to take the box out