NSW. Cool, a quick search of the rta site on google has yielded me this
pdf (right click and "Save as") which in summary gives the following guidelines for use of new wheels:
- offset cannot be reduced by more than 12.5mm on each side (that means you can't go smaller than +43mm)
- Outside diameter of wheel/tyre combination must not be more than 15mm greater than that of the tyre size with the largest OD on your tyre placard. What tyre sizes are listed on the tyre placard of your 2.0i?
- the load rating of the new tyres you are putting on the car must exceed that of the lowest rating on your tyre placard
- the speed rating of the new tyres must be higher than 140mm
- no part of the wheel/tyre combo can protrude outside the extremities of the car body
Anything outside this will require what many refer to as an engineers certificate and the run around with blue slips and what-not.
Bear in mind that the document referred to is dated November 2003 (Rev 4). I don't know if there is anything later.