SLSF 250-265, EMD NW2 SLSF 300-304, EMD SW7 SLSF 305-314, EMD SW9 Notice how in the early Frisco diesel locomotive diagrams, the draftsman tried to make the drawing look very much like the real locomotive. The evolution of models as time moved on soon threw them a curve ball, however, as the later "phases" and/or newer models often had revised body features. On these three EMD switcher models, notice how the draftsman got the headlights and the cab windows correct for the NW2, SW7 and SW9 models, but he/she blew the hood top to cab transition sections on the drawings. The early NW2s had the step transition as shown on each of the diagrams, but the later NW2 phases had a smooth transition to the cab, as did both the SW7 and SW9 models. Perhaps these errors led to the later "Vest Pocket" diagram books only having elementary drawings of the individual locomotive models. Ken
