I think the important part will be to show/prove registration history. Even better if interstate registration was current.
I agree with Boxhead, I expect the roadworthy will be useless.
I don't expect you will have any problems with registering an old car. It's the new ones that are a pain in the backside.
I know in QLD you can unregister an ICV(individually constructed vehicle) and just need roadworthy to re-register it again in QLD. But I wouldn't want to test that out.
Anyway, a quick call to rego authorities will get a quick answer to what the requirements are. Remember to mention it is an ICV.