I am in the process of up grading everything on my bass and bought these tunners along with the hipshot bridge.Everything I looked and said need to drill out the tunner hole to 9/16 of an inch. DO NOT DO THIS FIRST. I bought hand creamer and gave each about 4 turns wit moderate pressure and the bushings feel right into place. Ii really like the the way they look and how smooth they are. I will post pics when I am completely done.