when i bought my wrx, it came with the auto dimming mirror + compass. it's one of the optional things you can get when buying your new wrx, but i dont really have a use for it. i want to switch it to a stock rear view mirror. anyone know how i can do this? there are wires running to the roof and stuff. is it possible to do a swap?

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Yes, all you have to do is pop out the map lights. Behind them you will find the connector where the mirror harness is plugged in, just unplug it. You can then remove the mirror from the cam-lock mount by turning it counterclockwise and pulling it off, and install the standard mirror the same way.
If the replacement mirror is loose after you install it, take it off and remove the metal spring in the mount, and bend that spring to tighten it up.
Once you have replaced the dimming mirror with a stock one, you can sell it through the classifieds to get some money back. They are often sold through the classifieds here and at NASIOC as well as on Ebay. You can check around to see what the going prices are.
In fact if you check the classifieds you can probably find a stock mirror for sale as well, for less than a dealer would charge.