Thanks David, total agreement.
Grand Prix only means "Big Prize" and historically there are a good number of times in Europe where there were a number of Grands Prix in the same country in the same year. A Grand Prix of the country could also be held. eg GP de France, as well as a Grand Prix at Angloueme, Albi, Caen, Dieppe etc etc.
As far as I know (and am likely to be wrong) there was no requirement in the "good old days" for a GP to be authorised by any hierarchy, so I guess that the Ohakea event may fit that. However we like it or don't, it was the 1st Grand Prix so named in NZ, and as David says the Ardmore event was named as the 1st INTERNATIONAL.