These fiberglass tops seem to first show up in photos in the mid-1950's just before Conoco's 1957 introduction of Royal gasoline. Conoco used red accents for premium gasoline and green for regular gasoline, so I think gasman's comment was referring to the regular gas pump. While I don't have a color photo to offer, I am pretty sure you will see a green and red top at the same time. Here is a photo of pumps in the 1953-1956 time frame (when Super was offered) and I am pretty sure the pump on the left has a fiberglass top.
Andy
