Try again and toss some heat into the equation for good measure, just keep it localized to the screw/nut and minimize exposure to the box itself as I'm sure there are some rubber seals in there somewhere. If that doesn't do it, pulling the whole thing to work on it on the bench isn't going to do any better for you. If they're that seized up, using a big cheater bar or something to that nature is going to twist the screw in half before it does what you're hoping it will do. Just keep at it, mine took a few tries as well. <img src="/forums/images/graemlins/kewl.gif" alt="" />