Aren't you doing this with Mal?
We used a Hilux Diff and got a pretty decent head from Steelie Gears. It was $1100 for the housing and diff head, and Mal shortened it etc pretty well.
As you may know, the problems you will have is that the diff will be unsprung weight, and at-least in my install, the diff is very slightly angled downwards towards the front, which does something but I can't quite remember what.
How much was the LSD?