Differential Drain location

Hi, I have a 2005 GEM and want to change the differential oil. The service manual just gives the fluid amount and no instructions on how to do the procedure. I can’t locate any plugs except for the vent tube, I did notice a round black plastic type cap on the differential opposite the motor location not sure if this is the drain/fill location. Thanks in advance for your help.

Greg

Received the answer from GEMmechanic, it’s located on the very bottom of the differential, the black differential cover has a rubber plug on the passenger side. Oil has to be suctioned out. Thanks for your help and hope it helps others.