I need to service the differential

Here is a guide that will help with step by step instructions:

https://www.2carpros.com/articles/differential-service

Here is a video on a larger truck but it is similar:

https://www.youtube.com/watch?v=hpcxcnKbVto

Below is the process from the manual that shows just how to remove the fluid and does not require you to drop the cover. However, I would always remove the cover just so that you can see what is in the bottom of the housing.

Please let us know if you have questions. Thanks