I hope I don't throw a wrench into the equation but keep in mind (as I have built these type of rods before) to cut down the butt end of the blank so that you can place it in the proper size tube when the fighting butt is attached. I am working on a 8 wt. 4 piece now and will be doing the same to assure each blank is the same length for transporting. Cutting down the butt end (an inch or two) may also take away the problem you are having with the fighting butt.