So last year they had a fiddle with the system classes & whatnot
Majority of the info you want is here : https://www.nzta.govt.nz/vehicles/licensing-rego/
though if you're like me & your car make/model isn't listed then there's not much info specifically relating to "Classic cars" or "Vintage"
So I asked directly via NZTA Facebook page & received the following information via PM
Posting this info in the effort it may help or be informative
if you spy any private info that should not be shared or this is in the wrong section/useless then feel free to let me know or delete & I'll happily edit or amend
information correct at the time of posting