Your emissions equipment will need to be of the same standard or better than the car came from factory.
a 90's car is unlikely pass any road authority even with engineering with a carburettor as a replacement for EFI, even if you can get it to show similar or even better emissions.
If you really want the carb your better of getting it all rego'd and certed with EFI then swap over to the carb after.
Being in NSW, I doubt you'll get past EPA testing/Roadworthy inspection for your application for rego etc with a carburettor regardless of how new it is or the emissions it can do if the car came with EFI standard.