My understanding is all early standard Vks have the 8 bolt salisbury, later ones 1985 onwards im pretty sure it is, have borgwarners in the sixes, not sure about v8s but im thinking borgys as well. The standard Vk 6 has a smaller diameter tailshaft then V8s, they have the larger diameter ones- same diameter as VL and VN VP etc, but the flange on the diff is the same for all model borgwarners so reagrdless of shaft diameter it will bolt to the diff obviously providing that the shaft is for a borgy.
So you can Bolt a Vl Rb30 shaft to a VB-VK v8 shaft but not 6cyl. (although have heard that some EFI 6s have the larger shaft too)
Or in the original question, you can bolt a VK N/a shaft to a VL diff, but your car already has to have had a borgy under it, otherwise you have to get your self a rear Vl shaft if its a V8 or late Vk 6cyl model if its a 6.