Judging by
ER's card (esp the cars), the building appeared to me to have been built perhaps even 10 years earlier than 1938..and it turns out that it almost was 10 years (even LAC assessor info isn't always reliable)....
LAT July 14, 1929
As for the "AM" sign--it's for the the builder's "Austin Method" mentioned on the reverse of the card...
Automotive Industries Vol 43 (1920)/
from "Austin Standards for Railway Buildings" (1918)
Prior NLA:
LAPL
From
http://forum.skyscraperpage.com/show...postcount=2991
And more on the intersection of Wilshire & Robertson:
The northwest corner:
http://forum.skyscraperpage.com/show...ostcount=10069
The southeast corner:
http://forum.skyscraperpage.com/show...postcount=6898