Lordy, I don't know how often this must be repated.

Australian manufactured sedans from July 1976 used the Armstrong strut assembly & the PBR brakes.

Key words
Australian built/manufactured/assembled
Sedans [& only sedans.]
from July 1976.

All other body types were imported for the full 120Y model run.
Like the other models, ALL sedans up to June 1976 used the Jap spec mechanicals.
I can't be sure but it's possible that some sedans were still imported during the Aussie assembly period, ie, there is no guarantee that a July 1976 or later sedan is automatically an Aussie built one.