I bought an EZDown tailgate damper. The instructions say to remove a bolt from the tailgate. They show someone using an allen wrench to do it. A 3/16 allen wrench fits, but the bolt's too tight. There's what looks like an adhesive between the hinge and the tailgate. You can see it in this picture.
There's no way an allen wrench will loosen this--it'd snap. Any suggestions on what I can try?