Releasing the two clips is tricky and will likely take multiple attempts. Take your time and don't try to force the clips free, or you may break them.

Insert the flat end of a spudger at a downward angle between the top edge of the front and rear shells, near the viewfinder.

Push your spudger into the gap and lower it towards the back of the camera to pry up the front shell and release the first clip.

Repeat the process on the other side of the camera to release the second clip.