As a boy in the late 1930s, he received a scholarship for four consecutive years to study each summer with Thomas Hart Benton at Kansas City Art Institute.

He also painted scenery for movies such as The Shoes of the Fisherman for which he recreated the panel about the life of Moses, and parts of the Last Judgment by Michelangelo, for the interior of the Sistine Chapel (MGM Studios).

He was a lifelong Democrat and a committed Christian, who even painted Christ's Crucifixion (which hangs in England's Coventry Cathedral) and Resurrection (which is in the permanent collection of St. Luke's Episcopal Church in Sedona).

[The Disneyland Railroad Grand Canyon Diorama] was painted under the supervision of seasoned Hollywood scenic painter, Delmer Yoakum.

Del and his artists used over 300 gallons of paint in 14 colors to complete the realistic depiction of a day in the life of the Grand Canyon.