Abstract: Conversion of a fuel pump computer price variator from a three place to a four place unit volume price range and comprising an auxiliary higher place take-off shaft parallel to and having a coaxial gear in engagement with the variator cone gear, an additional summation differential mounted at the top of the variator coaxially with the cone gear and substantially within a stepped dome-like projection of a modified cost variator cover for combining an auxiliary higher place price output to the conventional three place price output, an idler gear in operative engagement with and mounted on a lever for pivotal movement about the additional summation differential for selective engagement with one or more take-off shaft driven gears, and, auxiliary price posting shutters connected to the lever for displaying the higher place price setting.