studs?
6 long bolts across the front
5 shorter bolts along each side
2 fat bolts in back corner going up through bed and into shell
Which ones are you having trouble with? If something is spinning, and you can't get some vise grips on the spinning part, you are going to have to cut the head off and deal with it once the shell is off.
The only nuts on the entire shell are not really nuts, they are captured "nuts" that are attached to the bed rails. If they are spinning, put some vise grips or something on it to hold it.
If it's something different from what I've said, I think you are on your own.