If replacing the dome lamp bulb, you should install the dome lamp bulb to the socket. If replacing the reading lamp bulb, you should install the reading lamp bulb to the socket. Then, you should install the reflector to the dome lamp, ensuring the retaining tabs are fully seated, position the lens to the headliner with the horizontal tab facing forward and the horizontal tab above the headliner, push the lens forward to seat the tab, push upward on the rear portion of the lens, seat the rear lens retaining tab and pull down on the lens to ensure that the lens is secured to the headliner.