http://www.direct.gov...alasset/dg_065254.pdf
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Vehicle registration certificate (V5C) – this must clearly show that the vehicle was made or first registered before 1 January 1973. If you do not have a V5C, or if you think the age shown is incorrect, you will need to produce a dating certificate from a vehicle enthusiasts’ club or evidence from the vehicle manufacturer.
(If the V5C indicates that the vehicle was registered from 1 January 1973 up to and including 7 January 1973, we will let you register it as a historic vehicle, based on the assumption that the vehicle would have been made in the previous year).