The two teams combined for five tries in the final 23 minutes as both sides threw caution to the wind and defence went out the window.
As the game descended into an open, end to end thriller - which resembled sevens more than union - Wellington thrived. They were clinical, decisive, pacey and daring and well worth the win.
Ultimately, it doesn't change anything for Wellington who are still getting relegated and have still had their worst ever season in the ITM Cup. But what a way to go out.
North Harbour earned a bonus point for their four tries but, with Southland grabbing a draw against Hawkes Bay, it was not enough to sneak into the semifinals.
Harbour will be disappointed with their performance at set pieces and their discipline. The visitors only conceded six penalties in the first half, but five of them were in kicking range and it proved costly on a day where Wellington first five Willi Ripia couldn't miss.
Both sides were too often careless in possession with turnovers a common theme and running rugby the order of the day. But it was exciting, and up until the 80th minute it was difficult to predict which way it would go.
Wellington No 9 TJ Perenara was Wellington's best and he capped of a great day with the final try of the match. He also saved a certain try with a sneaky turnover early in the second half which was a huge momentum shifter.
Wellington captain Brad Shields said it was the perfect way to end a forgettable year.
"It's been a rough season but to finish off like that and put 50 points on the board is pretty relentless," said Shields. "We've let other teams off a couple of times this year and the boys have been working really hard to get it right. To finish the season on a high is really cool."
Wellington 58 (Jackson Garden-Bachop, Victor Vito, Brad Shields, Vaea Fifita, Ross Filipo, TJ Perenara tries; Willie Ripia 3 con, 6 pen; Ross Filipo 2 con)
North Harbour 34 (Pita Ahki, Matt Vaega, Raniera Takarangi, Tevita Li tries; Matt McGahan 2 pen, 3 con; Daniel Halangahu con)
Halftime 15-17
