how do you go about shortening the hilux diff and getting the centre to end up in the centre, as it needs to be shortened around 100mm and this would all need to taken from one axle would it not?

are there wider diffs that you can use the axles from to get the pinion centred again?

this is the good thing about the BW78, you can swap axles and shorten the longer one to end up with the pinon in pretty much the same place as stock