There is no need to remove its rubber feet since it is held together by only one screw.

Wiggle the grey part of the top to remove it by pulling it towards you(away from the scroll wheel).

Do not pull the grey cover towards the top and do not pull the part near the keys.

Reasoning by Jacob Hickey "because in the internal top part of the mouse where the buttons/scroll wheel is, there’s hinges-like “tooth” that’ll snap if you do pull on it. It’s like opening a jewelry box that has a hinge on one end of the box… if that makes sense…"

The image is what your mouse should look like in the end.