Here is what I do.

Get a steel punch that has a nice square flat tip on it. Go in through the opposite side of the bearing you are trying to remove. Go through the opposite bearing, through most of the spacer, just short of the seam between the spacer and the inside edge of the bearing you are trying to remove. Use it as a lever on the spacer to move it slightly to the side. Usually one or two good pulls on it will give you enough clearance that you can catch the edge of the inside bearing surface. Gently tap it a couple of times to get a little nore clearance. Re-align the drift to get a better purchace on the bearing, a couple good wacks will nock it loose. If you are able to do one side then 180 degrees, directly opposite and hit it again go ahead. You should never touch the bearing races in the wheel with the drift. You don't want to mar those surfaces. once one is out, pull the spacer out and the other bearing is easy. Make sure to support the wheel so that nothing gets bent while hammering. Pay special attention to the brake rotor.

When driving in the new bearing, if you do not have the appropriately sized driver, use the old bearing that you removed. Lay it on top of the new bearing and tap away. Go easy at first to make sure that you are straight.

Careful using brass drifts against hardened steel. They can send little slivers of brass flying if you are not carefull. Not good for the old eyeballs.