patrols)suspension conversions can be done, prior approval and an engineer are required. diffs cannot be increased by more than 50mm, tyres must remain inside the guards, bumpstop height cannot be greater than 1/3 of vehicle specs the suspension is coming from. welding needs to be approved, original suspension components need to be used, aftermarket components required need approval also (adjustable isnt legal in queensland)
bundera/hilux
bundera/ifs
patrol/navara
etc...
just get approval before anything else, before spending money. they will give you the run but if u got approval and in the build process get photos and plenty of official signatures (welder, engineer, mod plater, etc.) they will pass it straight away.
DOT will pull you over and fail you for something, they are crunts, its their job.