I use a piece of pipe, and weld pieces of square key stock onto the outside of it at the proper locations. It helps to have a nut off the axle to use as a fabrication template. Put pieces of key stock the right size to fit the slots in the nut into position, held in place by a radiator hose clamp, then slip a piece of pipe into the middle and weld or braze them to the pipe. Drill a hole into the other end to accept a slide handle made of 1/2" or bigger round stock.
Jerry
