Ok,
You may have to gring some material off the 4.11 open casing to be able to fit the VLSD. Not a problem, but be prepared for that.
Being a Subaru Master Tech you know to use matching side bearings (if you do not replace them), i.e. the races and the rolling elements must be pairs.
Also, you will have enough adjusting plates to get the preload and both the tooth pattern and the back lash correct.
Enjoy
,
Tapani
edit: PS I checked the preload w/o the ring gear and the side seals.