I have taking my col. apart to tigthened the torx screws and have found the wedge in the upper shaft appears to be broken , the short end is missing and a piece added in the slot to make up the differance in length I will order a replacement . My ques is how does the wedge seat in the slot . Is it curved side away from rod & does the longer flat edge go face down or up in shaft . 2nd DR. rebuild lists locking wedge bumper #6521178 do you have any idea about that ? Pics would be greatfully appreciated . Thanks