Guys.....the trains I remember working thru Livermore were 401,402,406,408...I use to take 52 down to Tracy and saw these trains a lot...there were second sections on some of these trains.
406 was tge refer block out of San Jose, 401 and 402 were tracy-S.f. trains and was so was 408.
Traffic took a nose dive when the freeway was completed over Altamont pass...One could go to the ready tracks at the roundhouse and see what trains were called and what power was assigned. SP had no rule book for power assignments and any thing that was on hand could be see working Altamont. The WB beet trains drew the power as these trains were usually 5600 tons...when more AC's arrived, two could handle a beet train WB, but other wise, as many as four engines could be seen working the beet trains. I caught only a combination of a 2-10-2 helping a 50 car beet train with a GS as the road power..Eldon Lucy caught a 406 train headed EB with a AC on the point and a pair of 2-6-0's cut in as the helpers out of San Jose.