Drivers side front differential leak

Have an oil leak that started all of a sudden at the shaft end of front drivers side differential 99 tahoe. Can new seal/bearing be repaired on vehicle? I do my own service but have not did this before. I will be checking to see if a vent line is plugged also. Need to see or be told how to take off the oil seal and bearing from the drivers side front shaft at the differential. Schematic would help.
steve