PS: Here's an excerpt from the Gov's new fuel efficiency requirements which commenced Jan 1st 2025:
Its not one size fits all but instead a tailored CO2 reduction per each individual importer
IMO the next move will be , like Europe, to charge rego based on CO2 emissions rather than the current # of cylinders. Some European countries have a benchmark of 150 gms/klm CO2 with stiff rises in rego above that. This has drastically depreciated the value of older fuel guzzlers.