After finding a document about the Veeder Root computer, and staring at the mechanism, I was able to rest the desired price per gal on the range plates. (Note: document lacks an important detail for a first time user that range mechanisms are on cam-like locks and gear set swings.) BUT ... how do the price per unit wheels get to where they correspond properly? Toothed levers that appear to be fixed engage the gears at the bottom of the wheels.