You take the horizontal shaft (the one coming from the gearbox) off and then its pretty straight forward to change that bearing.    

You got lucky as you don't need to remove any flighting to do the bottom bearing on the vertical auger.   The top bearing on the vertical auger is a real joy to change, lots of stuff has to move to get at that one.    

Even worse than that is if the shaft in the bottom of the vertical flighting breaks, then you get to tear the whole unloading auger and tube apart.  BTDT


 If the bearing went out you probably need a new set of gears too.