quote:http://www.brunswickbowling.com/uploads/images/1051/High-Diff_Symmetric_Core_Drilling_Instructions.pdf4L or 3L or 2L depending on your style of bowling.--------------------Nick Smith ... A.K.A. Les Badder™Brunswick -=- PBA 03-06http://www.BrunsNick.com¡Viva la nación de Brunswick!