I just got this pic from the machinist who is cleaning up my rockers and boxes; it's a tool he rarely uses any more because most riders now replace the old rockers with new pieces that have roller bearings for the contact surfaces. See that semi-flat surface on one of the arms? It was rusted, so he cleaned it up. Later on (years from now) when I punch this engine to 93", I'll replace them with the roller bearing style rockers, along with other engine upgrades.
Here it is in action: