I assume you mean the races need to be installed in the hubs, and if so, try warming the hub by whatever means you have handy. I'd put the bearing race in the freezer for an hour or so, put the hub in the oven (while the wife is not home if you value your life) and heat it to (around) 200 degrees and the race will drop right in. Keep a brass drift and a hammer near "just in case" and you won't have any problems. But you do need to wait for the hub to cool before tapping in the seals.
+1 on that. No need to press anything, expansion by heat and shrinkage by cold does it easily. Just make sure you have cleaned the hubs out well (grease) b4 using the oven! A gas burner also does it but its easy to overdo the heating with that and the race will loose it's hardened properties.
I've gotten them out with a punch, but my favorite method is now to simply weld a bead directly on the old race. The weld causes the race to contract and it will fall right out.