The rockers are forced up against the shaft so the oiler slots/holes would be on the bottom to make a wedge of oil between the rocker and shaft. I took my 6 apart and it was seriously coked (dried up sludge) but still ran fine. I bet my rockers are plugged to, just getting into it. I believe there is a freeze plug in each end of the rod and if you take them out you can clean them easily.
