On the caged square nuts, how do you get them out if they turn inside the cage? I got them to loosen a bit, but then they both turned, and I can't stop them from turning. I tried wedging some thick shims alongside the nut to hold it in place, but that didn't really work, and with the cage and location, it seems impossible to get anything on them to hold them in place, or even to weld the nuts to the car so they can't turn.
I need to get the rear bumper off before I can have my patch panels installed, and I need to get the front bumper off before I can have my engine compartment painted, and there are 2 bolts on the front and 2 on the rear that are giving me trouble. Rounded the nut on on of the bolts up front going through the frame rail, and the other goes through the radiator support and it's impossible to get an impact wrench on either side, and I wasn't able to get enough leverage or force with a wrench and a breaker bar to do anything with it. Tried a nut splitter, which ruined the nut for all intents and purposes, but failed to finish the job. I've resorted to grinding the head off the bolt through the frame rail, it's a slow process, but it will get the job done. Unfortunately, that method isn't even an option for the other 3 bolts.