The top corners of the faceplate trim are slotted up underneath the faceplate.

Lift the bottom edge of the faceplate trim and thread it up and over the thumbsticks.

Pull the top corners of the faceplate trim out from underneath the faceplate and remove the faceplate trim.

To reinstall the faceplate trim, slide its top corners under the faceplate and over the thumbsticks, then push down along the edges of the trim to engage the clips securing it.