It isn't super early. The HZ ute on the brochure is IXD-457, that is IXT so it is a reasonable while after. There was a Supermint press test van built in the middle of September '77 but it had rego SXO-293 and I think that is a SA rego number? It's chassis number was over 01000A, was L31 M41 air, steer, DL7.
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