I have a Fender American Series Precision which I purchased used, but did not get the truss rod wrench. Now that the weather is drier and I have a bit too much neck relief, I want to tighten the truss rod to lower the action. However, I find that I can't get an allen key into the teeny-tiny access pocket that is at the top of the pickguard. I've adjusted my Godin BG-5 and Lakland Skyline 55-01 basses without any problems, but they have a much larger access cut-out in the body to get to the truss rod than the Fender does. Three Fender dealers have "declined" to order the actual Fender truss rod wrench for me. Nor do they seem to know what size it is. I guess there's not enough margin in small tools for them to bother. No doubt they're trying to ring up a sale and do a set-up for me, but it's an easy adjustment and I can do it myself as long as I have the right tool. Is it the long ball-end wrench with the red "T" handle that I'm looking for? I'm not sure. My question is: What is the size of the allen key required to adjust the truss rod? I believe it is an english measurement, not metric. The otherwise excellent Fender set-up document does not reference the size of the truss rod adjustment tool. If I buy an ordinary allen key of the appropriate size, I can hack-saw the end off to the appropriate length or maybe just buy a ball-end allen key of the proper size. Thanks in advance for your advice.