Pacific Electric Railway Post Office/baggage car in San Pedro Street, L.A., circa 1950

One notes the water tank on the roof of the building in the background. This car was built by Brill in 1915 as Portland Eugene & Eastern 452.  It became Southern Pacific Railway 771 after a short period and was rebuilt as Pacific Electric 1405 in 1929.  The mail facilities were removed in 1950; it was withdrawn in 1952 and scrapped the following year.  A close-up view of it is here