Cab hop is most likely the Buena Park Hauler (a City of Industry to Buena Park drag that was taking advantage of additional storage made available during the widening of the Santa Ana Freeway at this point in time). Note the unique lettering on SD9 #4358 (the second unit). SP SD9s usually had "Southern Pacific" written out in a single line across the hood, like the two trailing units. The lumber yard behind the train is today a fuel fleet depot, the GP9, three SD9s and SD39 are retired, and the freeway is being widened again, so that I'm not sure you can get to this spot north of Artesia Blvd.
