Several weeks ago, Mr Wilson (51) completed the challenge with wife Vicky Ashton, just to make sure he could manage the distance in tomorrow's Wanaka Swim Club fundraiser.
Mr Wilson is keen for others to join him on the swim, including people who are disabled but think they could give it a go.
The keen outdoors man lost the use of his legs when he injured his spine in a fall from a tree about two and a-half years ago.
He has remained active in sailing, swimming, snorkelling and para-cycling, although he took a break from most sport last year to recover from further spinal surgery.
In the swimming pool, he uses a sheath made of wetsuit fabric to keep his legs buoyant but in the lake or ocean, he wears a custom-made wetsuit and tapes his legs together.
Mr Wilson is also swimming to encourage daughter Emily (14), who is a keen competition swimmer at national division two level.
Mr Wilson joked he would probably take the longest time for the event because he had done little swimming since the Christmas holidays.
"On Saturday, I will be motivated by just being part of the swim club.
''I just want to be part of the action and involved in the process.
''Also, I did say a long time ago I wanted to swim around the island.
''That was supposed to be my goal this summer," Mr Wilson said.
Wanaka Swim Club committee member Gerard Gibb said the social swim was open to all comers.
"You have to nominate your time.
If you are faster than that, we will fine you for being smart and if you are slower . . . we will fine you as well," Mr Gibb said.
Entry for the swim, which starts at Waterfall Creek beach at 10am, is by gold coin donation.
