[Plums]

This is true, I'm a RAWS signatory and as such have to sign off Jap imports.

Gathering the evidence to form the evidence pack is not cheap (around 5 - 10K), and this is a very involved process.

There are heaps of requirements but here are a few of the ones that can cause you grief (and dollars):

Windscreen must have certain markings,
Seat belts,
All lights must comply,
Brake lines and system,
Fuel system,
Layout of internal gauges,
etc. etc.

One thing that might make the wheels fall off your wagon is emission testing. Firstly the cats will have to meet certain standards, then there is the actual testing itself.
Passing an emission is not too easy, in fact some new cars only a few weeks old may not pass. If the engine is modified you won't have a hope (generally).

As an example, I have been assisting an exhaust manufacturer who is trying to get an LS2 Malloo through emissions - to be able to market the system as ADR compliant . The only mod to the car is extractors and a cat-back system. The thing failed miserably due to poor cat light-up times.

Do your homework before you do anything, and don't even consider importing under the racecar rule (unless that's ALL you want it for)...