wiseco shows types and thicknesses if you want their rings to fit another piston, but i think that you are time and probably money ahead to do as dan suggests. i dont know kawasaki very well. i would check with the piston builder and see if that piston is designed to be cut for holes that the standard one has. those are to feed boost ports on the models i have been familiar with. some dont feel they are necessary and they probably do have limited advantage. lots of pistons are sent blank from windows so that tuners can put them where they want or dont want them. just check with the maker before you go drilling.