Just did the bottom end on TM K9B today. I hadn’t paid much attention to the gearbox layout before I found out some tuners don’t use oil. So I looked at bearing placement and realized that the C/L of the (4) main bearings (main shaft, secondary shaft) in the box are located above the oil level screw hole. The only way that the bearings can get lube is from splash. So it appears that lubing the gears and bearings is not a big deal.