My first thought was that those shots "taken from wall of Industrial Metal Company Sun Valley" was that that must be some mighty tall wall.... but then I remembered mention of a photomural of some sort... anyway, that Simon's was at the sw corner of Ventura Blvd & Laurel Canyon. Ventura Place is the long side of the triangle at left. ER: As you can see, the street atop the possible landfill is Laurelwood Drive.
The site of Simon's
Both pics Google Street View