At Chicago's Calumet Yard terminal on June 6, 1958, Nickel Plate EMD GP9 473 is mated to a pair of Alco RS11 units, 562 and (probably) 559. Unit 473 came from LaGrange in 1955 as part of class ERS-17-a. In 1967 it was renumbered to Norfolk & Western 2473, and in 1982 it was retired and traded in to General Electric on an order for new locomotives from that builder. RS11 562, of class ARS-18a, was delivered in 1956. It was sold to the Norfolk, Franklin & Danville in 1967 where it was renumbered 204; it was retired in 1982. David V. Leonard took this photo as these units were replacing steam power on the Nickel Plate's main line; the famous NKP Berkshires would be gone in a matter of weeks.