This is a DIY on a 03 - 08 Corolla on how to modify your rear view mirror from regular bulb to a LED.
By using the pick/hook tool to remove the cover gently then you will have to remove the bulb then replace it with a LED .
If you put the bulb in at first and it doesn't work then pull the LED bulb out and turn it around sometimes you get the positive and negative in reverse .
Put everything back and you have a bright light .
More DIY on www.corollacarclub,proboards.com