Jeffries was well known for the distinctive paint jobs and sculpted bodywork he created. Among his custom creations were the “Monkeemobile" and the Green Hornet’s “Black Beauty."
He worked as a stuntman, car builder and frequently painted race cars.
Jeffries did much of his early custom work in shop space that he rented from King of Kustom George Barris in Compton, Calif.
Among the many who Jeffries built or designed cars for were James Dean, Steve McQueen and A.J. Foyt. Jeffries was a devotee of the Indianapolis 500 and one year painted 22 of the 33 cars in the starting field.