ITR Rear Sway Install

[ViPER1313]

Can you get a pair of vise-grip type pliers over the nut then hit the pliers? What about a really long flat-head screwdriver as a chisel? You could also try tightening a bolt into the nut and hitting the bolt.....IDK if that will work though. Pictures are worth 1000 words - without seeing the problem I really can't offer much solid advise..