Ive just unearthed some VHS TV coverage of the NZGP most probably in 1986 but there is no identification of the year.
As Ross Cheever seems to be winning it (Im watching it as I type) in a black JPS Ralt Im assuming its 1985 or 1986.
Ken Smith is in the Apple Car Co Ralt and other drivers doing well are Paul Radisich, Dave McMillan and Ted Prappas.

Any ideas which year it was? Ill try and post some stills later.