"There's 600 people that live on the island, it sounds like most of them are coming to the game.
"They got their own club and team. They're the real deal."
The Barbarians lineup includes the likes of the retired Brent Dallison and Peter Rowe, who are Wanganui game centenarians.
Rowe also played for the NZ Provinical Barbarians in the opening game of the 2017 British & Irish Lions tour in Whangarei.
"Got a few current rep players like Wiremu [Cottrell], Lindsay [Horrocks] and Tom Symes," said McCrea.
"The rest are made up, pretty much, of every other club in Whanganui.
"The biggest represented club coming over is Counties. A bit of a buzz around their 50th anniversary this year.
"I think the age bracket ranges from 20-year-old's to say, mid-60's. Quite a broad range."
McCrea said the team would likely want to play the 80 minute match in 20 minute quarters.
"Not many of our lot are very fit. Obviously no training run.
"Pete Rowe, he's captain and coach, so he'll just put them through a walkthrough before the kickoff."
He added that of the 28 players, over 20 of them have been career forwards.
"It will be a hard case backline. Probably have Rowe and David Gower in the midfield, I think."
As well as Air Chathams providing a chartered flight, the team is well-sponsored through Ali Arc, West Coast Helicopters, Summit Electrical, Fleet Australasia, GJ Gardner and SJP Building.
This covered the team's equipment and unique playing jerseys.
"Great sponsors, everyone's been kitted out," said McCrea.
"Myself and David Gower designed our own crest through Display Associates.
"It's a Wanganui logo, the Baabaas logo, a crayfish and a wild pig. It's quite hard case.
"The boys will play in their club socks in true Barbarians style."
While the country only just saw its run of very dry weather broken on the weekend, on the island itself, which is 650km off the East Coast, conditions are expected to be a little cooler for the game.
"I think it's only going to get to about 17 degrees, long range forcast is just average," said McCrea.
"Friday looks pretty good so the boys will go fishing and diving. Booked a heap of fishing charters."
The Wanganui Barbarians fly out at 10am on Thursday, with kickoff scheduled for 2.30pm on Saturday.
The team is
1. Wiremu Cottrell; 2. Campbell Crossen; 3. Richard Shaw; 4. Jack Hodges; 5. James Marshall; 6. Daniel Horrocks; 7. Jack McCrea; 8. Matt Brown; 9. David McNab; 10. Lindsay Horrocks; 11. Matt Watson; 12. Peter Rowe (c); 13. David Gower (vc); 14. Brendan Bartley; 15. Tom Symes; 16. Trevor Gunn; 17. Chris Hay; 18. Scott Pedley; 19. Keryn Amon; 20. Will Lamp; 21. Sam Mallalieu; 22. John Carr; 23. Sam Medlicott; 24. Cody Wickham; 25. Mitchell Overton; 16. David Gordon; 27. Jamie Newell; 28. Todd Wise.
