Be VERY careful when changing lamps - the metal clip is anchored to the headlight assembly by a small piece of plastic and a screw and is VERY easy to break. It cannot be repaired and a new assembly is over $300

To get the rubber moisture guide off, you must unpug the connector going to the bulb first which is not always easy. There is typically bulb grease and dirt all over the connector and the tabs on each end of the plug are difficult to squeeze in all the way to get them to release the bulb. Once that is done, the rubber simply peels or pulls off the back. Grant's instructions are great and I modified them with additional pictures for my HID install doc which I will email you.