Several times in my bass and guitar owning history, I have gone to adjust a truss rod with an allen wrench, thought I had a good "bite" on the head of the nut, only to have the wrench slip a bit. Is there any advice/tricks of the trade in always getting a good bite on the nut so that there is no slipping or rounding off of the nut? I have a bass with a truss rod nut that is way down in the hole at the end of the neck, and I am really almost afraid to go down there with a wrench for fear of slipping and rounding it off. Am I developing truss rod nut phobia? Any advice?