For some reason I thought there was(another) plate around the jackshaft area, but as you say jon only around the breather.
I had a look at my block, and am mystified as to how oil could be getting that far, the area is totally open, the only thing I can think of is the oil pump is excessively worn on the driveshaft and oil is coming up the hole through which the drive hex goes in the block between pump and dizzy, but even then it would be spilling over out of the very open area around the drive spur on the jackshaft that drives the pump, very odd, it would then have to get past a(dizzy bottom) bush and a scroll, then another bush(in dizzy top) to appear where it does.
My advice would be to remove the dizzy and turn the engine over on the starter to see if the area fills up with oil through the hole which the drive hex goes in, if it does it is pump out time.
tabetha