WC SD45s 6529 and 6511 grind a stack and intermodal train up Byron Hill at Hwy. F after leaving North Fond du Lac for Chicago. This scene is now double track, part of CN's mainline through Wisconsin between Duluth, MN and Chicago. WC 6529 was renumbered from 6553, former BN 6553, built Nov. 1971. WC 6511 would become 7510, former BN 6511, built June 1971.