Ok thanks for the info, a bit surprised with your reviews of the place. I had a look at TripAdvisor and sold the place to my wife on their excellent reviews, I was already sold on the Ridgetop Tour and the Astronomy Tour.
We'll be staying in air conditioned motel accommodation and the reason I'm looking at early November is because they throw in an extra day for free. We both handle the heat ok but I hadn't thought of the dust (and flies).
We'll go via Adelaide as my daughter lives there and come home via Wilpena Pound at this stage, nothing set in concrete.