I'd go the other way Blocker. Things that make it not a Sandman:

All: 3 seat capacity, column shift, lack of console shift (4spd with no console).
HJ-HZ: lack of rear and side attachment hardware for headlining for Sandman van.
HX-HZ: Kingswood model ie N80 or N70, lack of interior light door switches.
HZ: 6cyl, not one of the unique tyre placards.

If it passes these then ask questions!

Lack of XX7 on Acacia Ridge is not the be all and end all: It could be an XU3 or something else that i'll reveal later.
GVM is a big trap, lots of XU4's out there.
Sandman was available on HJ Kingswood ute for the whole of HJ. HJ Holden Sandman ute was dropped early in 1976.

See how it becomes a big can of worms trying to condense it all?!