You start with a friction disc and fill it up. Check that the last steel disk do not fall off the hub when the clutch is disengaged. The stack is pulled out some 4mm when the clutch is disengaged. Fill up the rest with usually 2 friction discs. Check the distance between the inner and outer pressure plates to be between 3,2 to 4,8mm (1/8 and 3/16"), precheck can be done without or just a few springs. My slightly worn clutch has a distance of 6mm. There is a instruction page on KIWI indian. http://www.kiwiindian.com/#!clutch-assembly/cpwm

12 or 16 springs? I have always used all 16 springs. It may be slightly stiff on the pedal, but I haven't found any problem with that.