When you send the crank off for checking, polishing and possibly machining they will check all that. When you get it back it should have a little tag on it like below and you just order your bearings in accordance with the tags. The packet of bearings will have the main bearing shell with the appropriate size thrust bearing as part of it.
http://i42.photobucket.com/albums/e3...ps487e95d0.jpg
Garry

