Illinois Central's EMD SW7 units 1212 and 1209 guide a transfer run through Chicago in this transparency by David Leonard. The prominent billboard advertising the Enco brand used by Humble Oil (now part of ExxonMobil) dates this view to the 1960-1973 era, and in fact my brother snapped it on March 21, 1970. Both units came from Electro-Motive in 1950 numbered 9312 and 9309, respectively; in 1981 unit 1212 became Illinois Central Gulf 1500 and was rebuilt as an SW14. Unit 1209 became ICG 1508 in 1982 and was also probably rebuilt to SW14 specifications.