The 1956 CD lists System Auto Parks & Garages Inc at 630 S Grand Avenue, and Dagwood's Famous Sandwiches at 638 S Grand Avenue. I think we can see "DA ..." and "FAM ..." on the left. A slightly earlier incarnation of Dagwood's is just visible on the right of this circa 1948 LAPL image. If only it was zoomable.
LAPL
I'll have to see if I can find a better picture.