Removing a hex nut

[Floating teetH]

I'm fairly certain the truss rod on one of my basses is completely useless. I've tried adjusting it (as well as the saddles etc.) to eliminate a rattling problem which keeps mysteriously appearing and dissappearing. I've been reading around about this for hours but I can't figure out how to remove the hex nut from the truss rod. Before I start trying to pry it out, I wanted to be clear about some stuff. Despite the ever-so popular "righty tighty lefty lucy" thing, the hex nut becomes difficult to turn after I have gone counterclockwise so far. So shoud I have it more or less in the middle, where it seems most loose at least in the sense that it's easy to get the nut to turn before attempting to pry away at it?

 

[Turnaround]

DANGER! Don't go prying at the nut - it's just like any nut on a threaded rod. It's not going to come off by prying - at least not without doing some serious damage. If you are having that much difficulty, then you should take the instrument to a qualified luthier. If you insist on trying more yourself, move the nut to the position where it is loosest and apply a SMALL drop of penetrating oil to the nut as close to where it connects to the truss rod as possible and let it sit for a while. Then try to back off the nut again. If it still won't come off completely, give up and find a luthier. There are numerous things that might be causing the problem - too many to go into here.