Sorry to piss on your chips but from the looks of that machine, nice as it is, it's not a real candidate for a CNC conversion.

You would probably be a lot better off selling it or using it as a second op machine and starting with a clean sheet of paper.
What you want to do has been done before in various stages, simple linear rails for the bed and cross slide and a double drive system for the head as Steve says, motor to spin at speed for turning and stepped geared drive for barley twists etc.

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