Just did mine and have some comments that might be useful to someone.
1) I took Markovr's suggestion and fit a Falcon (AU) brake fluid reservoir on a VT master cylinder and bolted the unit to my VS booster. It was a straightforward swap with no issues apart from having to file down the little mushroom headed screw that comes out of the VS booster.
2) I can confirm that VT backing plates are a straight swap for the VS backing plates.
3) It seems that VT series I wheel hubs have the same ABS connection as the VS so should be able to be swapped. This would avoid having to use the shim rings to make the VT discs locate properly. If I ever need to change my hubs, I'll go VT series I.
4) I saw in one of the posts that the VT steering knuckle and VT lower control arm can be swapped in for the VS units. I didn't want to go this way because I am worried about the Ackerman being wrong for the narrower VS.