The reason we have led a good life post WW2 is that we have relied on the industrial rise of: -Japan -S Korea -China
and now its the prospective rise of India !
We subsidised the building of cars/spare parts because it was a hangover from WW2 when our national security was threatened because we could not import and BHP was nominated to lead Aus manufacturing then.
Assembling cars was always going to be our weakness because of it being labour intensive.
Nowadays , aluminium smelting/casting/machining is mostly automated (capital intensive rather than labour intensive)(Cad/Cam) and we have all the raw materials: Bauxite/Alumina Energy technical know-how global markets (high value aluminium finished castings can be air-shipped -just in time- anywhere in the world just try buying an aluminium block or a transmission housing for your car and you'll realise how expensive it is)
We also have FTAs with: -The USA -Japan -S Korea -China -Thailand
which makes up 70% of auto manufacturing
Its fine to say that we have a good life now, but, IMO, that won't last and perhaps the former Singaporean P/M was right: "that over time Australians will become the white trash of Asia" due to our laziness and dependance on others.