As Hood indicates, there are many ways to do it. I retrofitted an Emco 340 having in mind that it is not a hobby but an industrial production machine. Mach is installed in an industrial type computer, replaced DC drives with new servo drives, DC spindle motor with AC motor and VFD, added a PLC that controls many things, among them the hydraulic unit which comes with the machine. I would say I spent about $7000 USD in parts, and many hours wiring, writing the PLC program and just understanding what was going on. Still need to do the turret. Have been working with gang tooling.