Nichols served as Minister of Music (1960–72) at Church of the Open Door (4,000 attendance on Sunday mornings) while J. Vernon McGee was Senior Pastor. From 1972-75 Nichols became Musical Director of Campus Crusade for Christ. He and Doris traveled to Europe and South America supervising many musical groups. Later Nichols served in churches as Minister of Music in CA, OR, AZ, WA (1982 – 2009). While Nichols served at the Church of The Open Door, he became acquainted with the Los Angeles artistic community and the large musical productions at the church encouraged a member of his choir, an animator at Hanna-Barbera Productions to introduce Nichols to Bill Hanna. That led to a contract as musical director from 1963 to 1972 for Hanna-Barbera. He wrote score for the first incarnation of "Jonny Quest", and musical cues and arrangements for "The Flintstones", "Scooby-Doo, Where Are You!", "Josie and the Pussycats (TV series)", "Shazzan", "Birdman and the Galaxy Trio", "The New Adventures of Huckleberry Finn", Wacky Races, Space Ghost (1966 TV series), and the full-length feature "The Man Called Flintstone". During this time Nichols wrote film scores for World Wide Pictures. In addition to Nichols's big band compositions, arrangements, choral arrangements, anthems, and cantatas, Nichols has written or composed music for several operas, including: