The z axis was possibly one of the simplest to convert.

A bush was made to fit the original top bearing holder, then back drilled through the top casting for the ball screw. Having got a pilot hole, I use a 1 inch blacksmiths drill, from the top to enlarge the hole. The new double ball screw was located in the original holder. With a few new holes drilled the ball nut was secured. The top plate is 1 inch deep aluminium with a milled recess around the bottom. This allows the back cover slide in place, while being retained by the top plate. The motor plate slides in a slot allowing the belt tension to be adjusted