As you probably already know....Conoco, Mobil, Sunoco and Amoco were the owners of Martin & Schwartz in the mid-1940's when the M&S 80 came out. I suspect close to (if not) 100% of the production of the M&S 80 went to those firms. If you find a photo of another oil company using the M&S 80 in the late 1940's or early 1950's it would likely be because the station owner switched brands after the pumps were delivered. The attached 1951 article mentions that sales of the gas pumps from M&S were still primarily to those four oil companies, even though they no longer owned an interest in M&S. They each signed a 5-year contract to buy gas pumps from M&S as part of the agreement to sell the company in 1949, which ended up being purchased by Wayne pumps in 1951.