I think this has been discussed in detail here fairly recently, and a search will find this discussion. Some here have done this, and gave full details of how it works in practice. From memory, the main requirement is that you have to have owned and used the vehicle for a substantial period overseas. 
Nineties have not proved particularly popular here, although some people prefer them. My theory is that most Australians like to travel with so much junk that the ninety is not big enough, but the relatively high cost (compared to the 110 they were close to the same in the brief period they were sold here) may have also been a factor. Worth noting that most of the similar size Jap competitors have also been dropped from this market. 
John
				
			 
			
		 
			
				
			
			
				John
JDNSW
1986 110 County 3.9 diesel
1970 2a 109 2.25 petrol
			
			
		 
	
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