HI Alffie,
I have been looking at that myself, I am picking up my diff center tomorrow and when I do there should be a commodore ute there that they have installed one into, they then built custom shafts and the axles into the diff are 31 spline.
I am hoping to do some measurements to see if it will fit.
If the center fits without too much trouble, this would be the way to go.
Phil