3197-99 were purchased to complete the retirement of the Trainmasters on the commute runs. To stay out of California taxing in the 70s, these locomotives were used frequenly on interstate moves between LA and Portland on the Starpacers and back to LA on the BRLAT for the first six months of use.
First photo appears to be power for 1/376 ( 1/LABRT). A few loads of GM autos and lumber boxcars carrying freight forwarder traffic for Superior Fast Freight plus pigs make up the train. A second section will follow later in the afternoon and pickup PNW at the Roseville ramp.

The second photo was typical power on Oakland bound trains in the 70s on Sunday afternoons. SDP45s returning from Donner helper service and road service to Sparks. Be back to San Jose that evening or early Monday morning. SDP45s used on UPSFF/UPSFT/OASFY trains to the City will work back to SJ on the late Sunday evening commutes