It was also just nine days after Blair Furlong's dropped goal and the 12-all draw with Wellington which ensured the Ranfurly Shield would stay in Napier over the summer.
Ironically, on the day of the referendum, polling day rules meant all bars had to close at midday, and stay closed till voting ended at 7pm, after which the only people who could be served were house guests and their "bona fide" guests in private bars. It did nevertheless give publicans a chance to go to the game, the outcomes of which Mr Diack was becoming used to judging by the roar of the crowd at McLean Park just down the road, before he and the staff began filling the jugs in anticipation of the crowd which would invade the bar within minutes of the final whistle.
That was the Victoria Hotel, owned by his father, on a site from Marine Parade to Hastings St now occupied by the Beach Front Motel.
Still in the liquor trade, as part owner of Hawke's Bay Independent Brewery, Mr Diack still has vivid memories of the shield era, from first defence on July 22, 1967, to the last on September 27, 1969.
While, many often reflect on the economic boom that came with it, the hotels and the petrol stations benefited most, the impacts were widespread with even Marineland's heyday being able to be linked to the triumphant march of the Magpies. People came to Napier for the huge atmosphere, whether it be at the park or in the parades in Emerson St, where thousands lined the streets in front of closed shop doors.
The team would be in camp at the Criterion Hotel, and watch the parades from the balcony overlooking the street. Among those in the parade would be Mr Diack and staff, with a Model A truck, with a keg on the back, a hose and tap, and a couple of glasses to shout a few beers along the way. Back at "The Vic", where the bar would have opened at 9am, rugby fans were already getting in a few quick ones.
"The game was important," Mr Diack says, "but for some of them, the beer was more important."
The staff would have at least 20 jugs ready for the rush, but it was a daily exercise, the "swill" having taken its name from the rush as workers rushed from their jobs at 5pm during the week, to get a few down before the pubs closed an hour later.
After-hours drinking, however, was legendary, with stories remaining of the "knock three times," back-door entry to bars which at the front would have all the appearances of being closed. A glass cost 5 cents, and a jug was 33 cents.
Among the ongoing changes, from the days when liquor could only be bought legally at hotels, their bottle stores, RSAs, police and firemen's bars, and chartered clubs, to the modern era of beer and wine over the supermarket counter with the bread, milk and the kids' lollies, was the demise of The Vic. Bought by George Diack in 1957, it closed in November 1996.