Usually if it has been registered in the past (any time in the past) there should be a record of it in the system still, so it doesn't technically need the adr plates. I know in vic with my van (which came from S.A unregistered) it had been registered before so because there was a record of it and the build date, it didn't need the plate on it. because the enigine number and everything matched the old rego records it was all good and very easy to get registered. But security checks before hand are always good (which I did before travelling to Adelaide to get the van)