Bearings and races come as a matched set, and must be kept that way. Races are a semi press fit in the hub, and have to be driven out with a drift. The disc hat is bolted to the hub and loctite is used, so they are a LOT of fun to get loose, unless you have a good vice handy. You also need a grease seal which drives in the back side of the hub bore.

If your disc is loose from the hub, you should take it apart and retighten the bolts with loctite. I have found that if you don't use loctite, the high freq squeal and viration works the bolts loose.

Not responsible for advice not taken...