Sam, Open SWX, Go to "System Options, Data Options, Edit Standards Data, Expand "Ansi Inch", Expand "Hole Wizard Holes" Expand "Tapped holes", Pick "Tapped Hole", Pick "Sizes", Disable the ones you don't want. You can pretty much Disable anything in Toolbox. I have created several different standards for my various customers for tapped holes, bolt lengths etc.
Good Luck Mike Eckstein