The main advert is from the 1922 City Directory and just lists the address as the P.O. Building. The second entry with an address of 1419 Marcelina Avenue is from the 1929 CD, and the last with an address of 1421 Marcelina Avenue is from the 1940 CD, although the Torrance Electric Shop was already at that address by at least 1936. It was still there in 1956, and at 1421½ Marcelina in 1959. The last reference I found in the Torrance CDs was at 1778 W Carson in 1975.
1922 CD1929 CD1940 CD