There is a snap ring on the jackshaft on the RH side at the inside edge of the right bearing.
Move it close to the sprocket. clean the jackshaft so the bearing can slide towards the sprocket.
( jackshaft bearings have a snap ring on them also, but you shouldn't need to remove them unless
the bearings are frozen onto the shaft)
Move the whole jackshaft assembly to the right and lift out.
You may have to loosen the engine and push it forward if it has the 2-speed clutch on it.
Bearings are not pressed on. The 2-speed clutch and the drive sprocket are pinned on with roll pins.