Hi Anne,
Welcome to the Heartland Owners Forum and family. We have a great bunch of people here with lots of information and all willing to share their knowledge when needed.
I remember someone a while back painted the inside of their unit. Been a while, but will search to see if I can find it. I would think you would need to remove the center border on the wall. Think it comes off pretty easy. If I can find it I will come back with a link for you.
Meanwhile maybe some of our other members may know more.
Enjoy the forum.
Jim M
I found the thread. Check here and contact original posters for more information.