"Release the clip"

... (by hooking your finger into a tiny hole with no sightline, sharp metal edges, fragile plastics and no idea how the clip clips what to what or which direction it need to be pushed, pulled, hooked or pressed.  And when it has released the light unit will still not come out, so pull it a bit harder and then a bit more and then, with luck just before something beraks, it will come out - at one end - but still not enough to see how it is fixed at the other end.)