This is a No.6 Australian Arty tractor body (sitting on a F60L) known as the Bofors tractor, or LAA tractor and it belongs to Ron Fry of Seymour who found it upside down in a creek bed.
Some time later, and by pure luck (although he didn't know it at the time) he acquired a tired Chev C60S which I was able to inform him was just the vehicle he needed to go under it!
Here is a bunch more photographs, also showing how to identify a No.6 tractor cab.