As a first step if you haven't already read part 13.3 of the vic guide to vehicle modIfication:
These are both options of not meeting VSB 14 (NCOP and ADR's). The NCOP enables lifts between 50 and 150mm with an engineering certificate and lane change test results... (I think). This would be an expensive but only viable option to run 33's on a TJ and stay tikityboo.
Most people in VIC go with the VSI options and find engineering certs and lane change tests too much hassle or too expensive or have no clue about the shit and just do what they want when they want and what looks good to the eye goes on the car (I wish I was more like that a lot of the time)
I think option 1 is a better way to go but will limit you to 75mm lift + tyres. If you need 33's I'd say maybe consider a JK or other 4wd that comes with 32"s stock
I dont think the laws were grandfathered so I assume a lot of people are potentially in a place they don't realise with there existingly moded vehicles when the new laws were bought in.
There are some insurance companies that say they will cover you as long as you fully disclose all modifications (I think this says a fair bit about the arguments against the ADR's). However from my business law study I seem to remember that it is a condition of coverage that the vehicle be in a fit state for the intended journey. The next argument is where meeting or not meeting ADR's or state roadworthiness laws puts you in relation to fitness for the journey. There are some parts of Australia where meeting the easier parts of ADR's mean your vehicle is probably not fit for the particular track that is open for public access however 150mm with an Engineering cert is available... Is an Engineering cert an undue impost that causes people to not have there vehicles properly modified for the track idk...
I'd say the laws being new are still fairly untested and the cautious approach would be to stick with one of the options in the VSI or get an engineering certificate under the NCOP it may actually not be that expensive I have no idea. If you find your already modified vehicle outside of all the options id say choose an insurer that has vested interest in the 4x4 industry (Club for instance). Also make sure that you disclose all modifications and check they are listed on your policy.
In the meantime write a letter to your local MP share your disgust for the Nany state laws and let everyone with a 4x4 know how ridiculous they are.