Use a small knife and work around the edges, taking care not to damage the plastic. Pry up on it, and it'll pop out. Done it a couple times, when I've upgraded Centris 650 machines to Quadra 650 logic boards.
There is a hole on the back side. I'd use a hair drier to warm up the badge from the rear and as blunt of a tool possible to poke through that hole to push the badge off.