Assuming you meant bushings and not bearings?
So much of the process is good prep.
I can only give you my feedback on my own installation on a Commando.
I clear all paint from the inside of the bushing "ports" making them as smooth as possible. A
very light wipe of lubricant on the interior of the receiving wall and the outside walls the bushes.
The outside walls of the bushings can be smoothed out with some steel wool or 800 + grit sandpaper, being careful to remove as little material as possible for a proper fit.
I disassembled a gear puller, removed the claw arms and ran the pulling bolt thru center of the puller T-arm, through the swing arm and bushing. I I used two heavy washers on the opposing (interior) side and then screwed a nut on the end of the pulling bolt. Get the bushing settled into the start point on the receiving "port" of the swing arm then snug down the puller bolt. Begin to evenly pull the bushing into place while turning down the main puller bolt with a wrench.
Just keep screwing the bolt tighter, not too much resistance but not too easy either, no binding allowed. Keep pulling the bushing into final seating position.
Some say you can tap them into place with a mallet or hammer, I do not use to this method.
There are others in here who can explain bushing installation more clearly than I but maybe this will get you started.
Hope this offers some insight.