I had my passenger side cover repainted after I scuffed it on my garage door. I was able to remove it by gently using a plastic pry-tool that came in a kit from Amazon. I started prying a small section on the inside(towards the door) corner and then gently worked my way out till I could safely pull it off. Be careful, take your time, and it can come off without scratches.
Putting it back in is tricky too. Either the top section slides in first, then the bottom clips on...or vice versa. Can't remember. You will see the tabs on the back when you get it off.
Consider getting a kit like this if you like to DIY
Amazon.com: 5pc Nylon Master Door and Trim Removal Tool Set: Automotive