If you mean the black plastic "cup" behind the interior door opening lever, then you do not need to remove the panel itself.
Removing the cup is the first step in removing the door panel.
It is held by a screw hidden behind a plastic plug that needs to be removed using a sharp instrument. It is almost impossible to not damage the plug and it will fly out causing hours of searching ... before finding it sitting behind the lever
Two jewelers' screw drivers will work. One to pry and lift. The other to hold position while moving the first one to get more out. There is a small notch at either 3 or 9 o'clock that is helpful except that you wouldn't know about it until you have done it at least once and have bothered to look at the plug before reinstallation.
As usual, lubing the piece can be helpful if you ever have to follow the path again.
In removing the door panel veneer trim everyone tells you to lift the rear portion away and then slide backwards. What is not mentioned is that the rear retaining lugs must clear the retaining clips or it won't slide. The lugs are a half inch long.