I replaced a bearing in a 5 HP single phase Baldor motor. I simply set it on the table, and removed long screws holding it. Then I pried open the rear bell, being careful not to damage wires. Removed wires and pulled a shot rear bearing with a bearing puller.
I gently hammered the new rear bearing in place, using a water pipe and being careful to place all load on the inside ring and nothing on the outside ring or seal.
The front bearing turned out to be fine. I did not replace it.
I reassembled the motor and ran it. Here's a 16 MB .AVI video of it running, starting and stopping. Let me explain what you see and hear in the video. The humming noise is my phase converter. I run the motor from one of its 220V legs. Two loud BANG sounds are me turning a heavy duty disconnect on and then in a second or so, off. Then the humming noise stops as I turn off the phase converter. Then you see the motor slowly spinning down.