WP 917,918 & 921 have sam scheme ,Era Dec.1977 to end of WP:

By the mid-1970s, the Western Pacific Railroad, being short of working capital, elected to continue to run it's final four F-units instead of trading them in for newer power. In 1975, the alpha suffixes locomotive numbering were dropped. WP rebuilt Nos. 913 and 921 at Morrison-Knudsen while Nos. 917 and 918 were rebuilt at their own shops in Stockton. They were repainted green with orange stripes except for No. 913. No. 913 was chosen to be repainted in orange and silver with large Western Pacific across the side. 913 became the most photgraphed F unit in the west. They were assigned to power freight trains between Stockton and San Jose, CA such as on the Auto Parts Forwarder (to Ford Milpitas assembly plant), San Jose Manifest (to Stockton), or the San Jose Turn. These final four F-units attracted attention from the railfan community and were nicknamed as the "Fabulous Four". Locomotives 913 and 918 were retired sometime in 1982, and 917 and 921 lasted until Union Pacific took over WP. All four units are happily now retired. WP RR Museum has 917, 921; Calif. State Railroad Museum has 913; the Niles Canyon Railway has 918.