Toro 20017 PP stopped moving last week.

Removed cover from tranny and saw that the thin cover came off the roller bearing-ball assy...was caught in the gears.looked like this thin looking washer just sat on the bearing -ball Toro # 100-1048. cost $6.92. Will the whole assy need to be removed? I can't see how? Have assy on order.....will just try to get mower moving with out the whole new assy. Is there any thing better than"00" to repack the tranny?