I never got around to following so many peoples advice to stick a piece of pool noodle into the mast cup during transport. Failure to do so finally caught up to me after around 60 outings.
The balls decided to start falling out on a road trip rather than at the nearby bay where I normally go out. 60 MPH down the freeway when it happened. I had a sick feeling when I saw them missing knowing the mission was over
Much to my amazement, each and every ball was inside the cup!!! Better yet, the Mrs.'s was able to retrieve them by hand. Mission saved!
I did the remove the plates thing and sand advised in a couple posts twice (didn't have any decent sand paper) with less than acceptable results. They seemed OK but when I hit them with a leaf blower (use it to blow water out of t&s hatches and seat connector holes after rinsing) they flew out again. Again, all that came out managed to go into the cup!
Anyway, after looking at the plates I agree that enough sanding in the right spots should get them to work again. However, I think the actual problem is that the lip of the bearing race has worn down. So rather than spending $10 on gas to go get more sandpaper and spend even more time fooling with them I just ordered two new bearing plates (part #795330010) @ $9.29 each. Put them on and the bearings didn't came out hitting them with a spray hose and the leaf blower. problem solved.