I hope you are right Polly. Maybe try a short ride, say 10 miles, and pull the sump plate again to see if more pieces show up. If you haven't used gasket sealer yet, maybe skip it until you've done a couple such tests. If no more pieces show up, maybe the bits you just found were simply missed by the previous rebuilder. On the other hand, maybe the PO had discovered bits in the sump before the sale and removed those on top of the mesh in case you checked that becore purchase, but missed these.
I wonder if anyone here has a good way to check crank play with the assembled cases in the frame. I'm really trying to avoid saying it has to come apart, bbbbut, it does seem like a strong possibility. I'm honestly hoping someone chimes in and says I'm completely wrong.
Richard L.