Instead of buying an expensive die set for the #12 screws that retain the counterweights in place I fabricated a female die from a piece of 1/4 inch steel flat bar. I drilled a hole to #12 size then machine countersunk the hole a bit deeper than you would normally to account for the relatively thick counterweight skins. I sacrificed one of the bolts as the male die and used a nut as a spacer and a C-Clamp to push the screw into the female die. It worked out very well with no cracking or abnormal deformation.
