I've roughed out the cross slide now, I made it from Fortal as I wanted it to be as strong and rigid as possible while sticking to aluminium parts (I'll get everything anodized once it's finished). I also wanted enough material to be able to bore the cross slide for a 20 or 25 mm dia. NSK spindle for live tooling. I cut a pocket in the base to lower it a little and keep plenty of material around the tool holders, particularly the threading and turning tools. It still has a lot of detail left to go into it, but I intend to use the lathe itself to bore for the collet chucks and live tool, so I will have to get it running before I can finish that part.
I'm not getting anywhere conclusive regarding using Mach3 to control the spindle as a rotary axis for live tool use. Any advice from someone who has built a live tool lathe would be gratefully received!
Ps - Hesham - no luck on the lathe chucks from the Clisby lathe. Sad news - they are closing down. A shame - the lathes look really neat.