How do you remount a rear view mirror to the windshield on a 2002 X TYPE?

There is a little piece of metal to which the mirror assemby attaches. Remove that from the mirror assembly, clean off the old glue then purchase some mirror adhesive from your local auto parts store. It looks a lot like super-glue, but is a little more UV resistant and holds up well on the windshield. After you've attached the little piece of metal to the windshield, let it cure for however long the instructions say, then hang the mirror assembly from the mounting piece and re-attach the mirror. If any of the glue runs down the windshield, let it dry and scrape it off using a single edge razor blade or scraper.