Caption: Harder and harder to find on the mainline compared to years past, SD40's still hold down assignments on CN here and there, including working the hump at CN's sprawling MacMillan Yard north of Toronto. On a warm summer evening, just such a pair push a cut of cars down the pullback track at the north end of the yard: SD40-2Q 6020 (originally built as CN SD40 5114), slug 279 (ex-GP9 4452) and SD40-2W 5298, still sporting its original "factory fresh" stripes. CN 7500-series GP38-2's and 500-series hump slugs once held down these assignments for many decades (replacing the old MLW S13 and slug sets that the hump began with in the mid-1960's).