The waka ama fundraiser is his way of giving back to his hometown and Outward Bound, and he is motivated to help send even more people to Anakiwa.
Kaweka is the specially designed Outward Bound course for Hawke's Bay young people.
"Young people in Hawke's Bay deserve this opportunity."
Gunn has roughly 11 months left to train and prepare for his 14-hour solo waka ama adventure.
National waka ama champion Corrina Gage has been training Gunn in preparation for the big paddle. The plan is to build up to paddling 80-100km a week before the big crossing.
"I'm laying the foundations of my training with the local Takitimu waka ama club a couple of times a week," Gunn said.
"Everyone is very encouraging, and I'll be leaning on that support to help find a support vessel closer to the time."
Gunn said the more daunting task is fundraising to get to the $63,000 goal.
He is joining several supporters from Hawke's Bay, who also contribute to the Hawke's Bay Foundation.
The foundation is a fund that supports young people to attend the Outward Bound Kaweka course.
Foundation chairman Giles Pearson praised Gunn's mission.
Pearson said in today's ever changing and fast-paced world, Outward Bound equips young people to build confidence, resilience and self-awareness to better navigate and steer change in their lives.
"Gunn will be pulling on all the attributes to complete his 100km open water paddle," Pearson said.
"As a community foundation committed to the needs of Hawke's Bay, we are incredibly proud to support more young people on their journey to self-discovery."
Outward Bound chief executive Malindi MacLean said students find the course transformational.
"For the majority of our award-winning schools programme students, Outward Bound is three weeks of firsts," MacLean said.
Students have said the Outward Bound course provided a safe, encouraging and stimulating environment where they could rediscover themselves, examine their priorities and values, and push the boundaries of what they believe they can achieve.