Hi Tiddles,
I'm jumping through hoops at the moment with a Condor project on a type 3 chassis. My understanding is that if a car has been registered in the past, you should be able to get a roadworthy certificate and have it registered in your name for full road use. However, if it is classed as needing to pass an engineers certificate, you may need to abide by the Australian Design Rules here:
http://www.infrastructure.gov.au/roads/motor/design/adr_online.aspx
Find an engineer in your state who is licensed for light vehicles and ask them for details. My engineer in Bendigo has been great and helped me a lot. Basically the chassis stuff could be as per the rules in 1971 when my chassis was built but the body has to meet todays standards so I've needed to add side intrusion bars to the doors.
I hope that helps.
Dino.
