Can't help with the date but do have this a hand drawn map of the Club Circuit as used by NSCC in 1978.
Club were still using the full circuit including the loop part in 1979 / 80.

Think was first used in 1967 - has been mentioned on the Pukekohe thread.

Name:  NSCC Motorsport Day 1978 #08 p8 sprint regs and track planCCI22122015 (564x800).jpg
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