Grimme, what a great offer, Rhy's have played around with the Mistral pic, there has been a piece on NZ Classiic cars and wreck forum about the Mistral. Produced in Dunedin by Emslie and Flockton, in the late 1950's.. now must find the Advert
here is my copped version of your picture;
Where was the Hillclimb, a great view for those spectators ??