The fours drew their final game to tip the balance in Aramoho's favour, although had they tied with Paritutu they still would have won the regional on a points countback.
Paraparaumu Beach finished third, ahead of Stokes Valley.
Aramoho now have their sights on the national final in Palmerston North on the March 22-23 weekend.
Five of the six zonal finalists have been found with the last regional playoff in Gisborne this weekend.
Aramoho are two-time national champions and had a disappointing one-point loss to the Nelson club last year.
"Certainly it's good to be there and have the opportunity to be the top club in New Zealand," said Slight.
There may be changes to the team as Peter Belliss was unavailable for the pairs but can likely play in Palmerston North.
The Wanganui women's representatives were not as strong as the Wanganui East team finished last behind the winning Victoria club, with Paritutu second and Kapiti Coast third.
"We're just gutted. We only won one pairs and one singles," said team manager Kathy Garrett. "We had some near misses but it was just one of those weekends."
There was some consolation for Maria Klitscher, Marilyn Constantine, Sadie Head, Claire Ellen, Eileen Anderson, Anne Anderson and Robin Firmin, as they watched the men's games.
"The Aramoho guys did really well so that was a saving light really being there to share that with them," said Garrett.
"It was just a deserving win and good on them."
In the Premier 2 grade, the Castlecliff men's team will also progress to the national final after their victory at the weekend, while the Castlecliff women's team came second by just one point.