A couple of things I forgot.
No felt sole wading boots. Hiking/wading shoes may be taken by the folks at the NZ airport and chemically treated to keep Montana stuff out of NZ. Necessary nuisance and time delay.
Although they have wonderful coffee in the cafes, all lodging is equipped with electric water pots and instant coffee. All the toilets are 2 speed (something we need in the states).
Be sure to bring an electrical outlet converter made for NZ. The generic one I got at Wal-Mart had plugs for at least 4 countries, none of which worked there. We finally found one at a general store in Matamata for a few bucks. Jim