Here is a map depicting New Zealand before 1840 and the location of all the mission stations.
Source: Archives New Zealand Below is the full description of the map.
Map of New Zealand missions before 1840
Missionaries played a huge part in the signing of te Tiriti o Waitangi – from translating and interpreting the documents, to hosting hui at their Mission Stations.In December 1814 the first missionaries arrived in the Bay of Islands, where they established the first mission at Rangihoua under the protection of the local rangatira. In 1823 Henry Williams arrived to lead the Church Missionary Society mission. His brother William joined him in 1826. Both would play an important part in the Treaty signings. To strengthen the missions and protect his Māori converts from undesirable European influences, Henry Williams led missionary opposition to the New Zealand Company and other large-scale colonisation ventures. Williams favoured intervention by the British government, and CMS missionaries, Wesleyans, and the Catholic Bishop Pompallier (after an assurance that all religions would be tolerated), all welcomed the Treaty. Missionary influence in New Zealand perhaps reached its peak during 1840, when rangatira such as Hōne Heke and Tāmati Wāka Nene gave their Christian faith as their reason for signing te Tiriti. This diagram of the North Island of New Zealand shows the locations of various Mission Stations before 1840. Because of the influence of missionaries, the journey of the nine Tiriti sheets and where they were signed closely matches this diagram. It was drawn by C.N. Watson in 1951 for a school publication. Archives Reference: AAAD 700 Box 6/ 840