if you have the shaft out you can drive the bearing out by inserting a big wooden dowel in from the opposite side and tap the bearing out. there is a shoulder machined in the housing that holds the bearing from being driven in too deep. so you can't drive the bearing all the way through the housing of the block. If you tap on the threaded studs/the side where the clutch is with the little threaded rod that is in the center aka where the star nut or flower nut goes you can damage these threaded areas. You want to use wood or plastic over these parts if you are going to beat on them I suggest that you drive the jack shaft out from the sprocket side and protect the threads on this side as well tap it and don't beat the **** out of it. once you get the main shaft out there will still be a bearing in the case so now you take a big wood dowel or something that will catch the bearing outer race and drive that bearing out again don't beat it like a redheaded step child go easy on it.
Most of this work is kind of like being the village blacksmith without the forge and the anvil. take it easy and think of what you are doing before you smote your toys parts with the hammer, don't be like Thor and whale on it.
hope this will help
to get the bearing off the shaft I place the shaft in a vice so I can drive the shaft off the bearing not the best thing but again going easy it will come off if you have an arbor press it will come off easily with out all the beating screaming and cursing that can go with this sort of thing some day I'm going to get me an arbor press I just need to hit harbor freight when I'm not on the bike and tornado warning are out.