Some pics of cleaning up a rocker. Here is what a "good" used rocker looks like. It has had a lot of quality time with the cam and polished to shine with smooth undulations in the surface. Not much surface for holding oil when so shiny like chrome. Here are the 3 best rockers out of a used set of 12. I refreshed the worst of the 3 by using a flat slab of marble and sand paper. I measured variance to be 0.001" across the surface's peak. The front (engine side) is where the drop off i