If you don't have a chisel and you have a dremel, hmmm, I think there is something wrong. A hammer and chisel are the basic of tools. JMHO.
You could always just bite on the nut with vise grips and twist until you twist the stud in two. The next problem is going to be getting the stud out of the case. Granted, it will be easier to get a bite on it with the jug off but it will still be stuck in the case.
Good luck!
SP