He was born October 29, 1923 in Carter, South Dakota to parents William and Cordelia Creasey Chauncey. Neil grew up in Winner, South Dakota. He served in the United States Army 102 Infantry Division during WWII. After the war, Neil married Elizabeth Erk on November 3, 1949 at Blessed Sacrament Catholic Church in Rapid City, South Dakota. To this union four children were born. Neil graduated from the South Dakota School of Mines with a degree in civil engineering. He was a member of the Theta Tau professional engineering fraternity. After graduation he worked for the Department of the Interior Bureau of Indian Affairs from 1949-1979.
Neil and Elizabeth retired to Denison, TX in 1979. He joined, and served as past president, of the Texoma Rockhounds. Neil served as past president of the Chapter 1290 Federal Retirees of Sherman. He also taught Lapidary classes to senior citizens at Grayson College for several years. Neil was a member of St. Patrick Catholic Church.