[Ron Ramirez]

I think synthetic might be better...longer life, I would assume...

To reassemble: One small ball goes into the large shaft first, then spring, then other small ball. Then small shaft partway in, with three large balls put in place from the outside (not inside), then slide the inner shaft in most of the way while holding the large ball bearings, keeping them from popping out. Of course this assumes grease has been applied where needed first. Then push the inner shaft in all the way as you slide the entire assembly back into the keeper. Once it is all back together, the large ball bearings will keep the inner shaft from coming out. It's easier to just do it than to describe it.

Great job on cleaning that shaft assembly! It should now be good for another 70 or so years.