I know the letters pop off, but it looks like the bracket under them isn’t removable, so I wasn’t sure if it can/needs to be removed or if it sits on top of that letter bracket.

Your car has a base where the original RAM letter is mounted on a bracket. To install our RAM LED letter, you’ll need to remove the original RAM letter first; you cannot remove the base itself. After removing the original letter, install our LED RAM letter on the existing bracket.