I am getting ready to order some new knobs for my new sr505. I found some that appear to be the type used on the higher end Premium and Prestige basses. I want to get the right sizes and wondered if anybody knew the shaft sizes and if they are knurled, split, or what. I have not had the chance to pull the old ones yet and not sure I have a means to accurately measure the diameter. Any help would be appreciated. Thanks!