G'day Mr Beefy,
As far as I know back then the engineers at the factory, they just built two machines:
The front-engine model (The Tractor)
The rear-engine model (The Mini / Mini-Mow)
The "Javelin" was just a name they slapped on.
This manual I think covers most of your model
https://outdoorking-forum.com.au/fo...mber/624/filename/MiniTractor5and8HP.pdf