Hey guys, i have a ke10 it has a jap diff, same (different width) as the datsun1200 jap diff and centres are interchangeable, also ke20 is the same cause i have just put in a locked ke20 centre. i think the axle lengths vary between them all. You can also use a 120y jap diff centre. But i think they are all H145 diffs. Ke30 early is H145 jap, then some assembled in aus used the borgwarner diff mentioned here, i can measure centre of leaf to leafs for the different models for people if they wish. Ke20 an Ke10 are different stud pattern than the ke30 though. Ke30 and on same as datsun.
Sean