After around a month of searching, I have confirmed the location of this 57. While looking on a Historical Imagery site, I came across what seemed to be a dilapidated 57. Even though I thoroughly convinced myself that that was the 57, I still wanted to check. I did some research and came across numerous images of the 57 on the hill located in South San Francisco.
http://bitsofhistory.plsinfo.org/lar...fset=70&id=908
The Hill located in South San Francisco (Enhanced for better quality; Original photo is on the right)
After doing even more research, I came across a picture of what was Bayshore Blvd looking North towards San Bruno Hill (Currently Airport Blvd). I was surprised to see that the 57 had made a guest appearance in the photo!
I was determined to find a better image of the 57, so I looked through
http://bitsofhistory.plsinfo.org/index.html in order to find a nice image of it. I eventually came across this stunning image of a grocery store with the Heinz 57 sign peaking out from the right-hand side of the building.
http://bitsofhistory.plsinfo.org/lar...set=100&id=562
I am proud to say that I have found the 57's previous location. Here's a Google Earth Image showing important points of South San Francisco.
(Click on image to expand)