[cleszkie]

The nuts are held in place by metal "cages" that are pop riveted to the fiberglass top bed rail. What happens when the nut is rusted to the bolt is that the bolt will turn the nut until the metal arms on the cage are spread open or break off from being rusted and then the nut just spins with the bolt and you are screwed. Your best bet is to keep soaking the nut and bolt and slowly work the bolt counterclockwise and clockwise to slowly clear the threads without spinning the nut. Gradually you will be able to completely remove the bolt if you are patient and a little lucky. If you do get the bolts out, run a tap through the nuts, get new bolts, and use anti-seize next time you reinstall the bolts.