According to the Mall Hall of Fame blog, Del Amo was the 11th shopping mall in Los Angeles County. The caption to this picture (orginally from CSUDH) says
"A circa-1962 view of DEL AMO[pronounced "duh-lah-mow"] CENTER. Sears, the south anchor, faces the Hawthorne and Sepulveda Boulevards intersection seen in the fore-ground."
For the record, Jaime Del Amo (then President of Del Amo Estate Co. and adopted son of the Dominguez land grant family) joined the President of Broadway Hale Stores and the VP of Sears, Roebuck & Co. to announce--on March 19, 1957--that a shopping center called Del Amo would be built, at a cost of $40 million.
Not sure which of the bigwigs said it, but the project was called “the prototype for future shopping centers." For the first time in this area, according to the Los Angeles Times story, two large department stores were linked in a single project.