There is a special mirror glue you need to use. You can buy it in any auto parts store: Advance, Discount, Autozone, Pep Boys, wherever. They sell it in a one-mirror package. Just scrape off the old glue with a single-edge razor blade, and follow the directions to the letter. You will need some tape to hold the mirror up[ overnight.

Sometimes the glue is so strong, you will find that the mirror has taken a piece of glass with it. If this is so, reglue it to a different, completely smooth spot.

Good luck.

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Semibodacious Transmogrifications a Specialty

1990 300D 2.5 Turbo sedan 171K (Rudolf)
1985 300D Turbo TD Wagon 219K (Remuda)

"Time flies like and arrow, yet fruit flies like a banana"
---Marx (Groucho)