It's possible to remove and replace the bearings without a hydraulic press. You can take a piece of heavy steel pipe, (or even a heavy duty socket), that is just slightly smaller in diameter than the bearing. Place the end of the pipe securely against the outer race of the bearing, and use a hammer to 'tap' or 'drive' the bearing out and then back in.
If a press is available, or if money is abundant, I would recommend the press, but the job can be done without a press. I did it. The Haynes manual even lists this as a possibility.
