There is supposed to be some special tool, you can buy it if you like for aroun $15, or your dealer cn pull the radio out too, they should do it for free. I used 2 different sized allen wrenches. It you have an allen wrench set then just keep trying them until one works. It really is not too big of a deal, just remember that you may not find one that fits perfectly for both sides. I believe the right side took a smaller one for me.
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