Having banged my head against another forum member's ATC (Matron!) for a goodly while, I'd suggest that you'll want to research exactly the control/state-machine/timing required by the ATC and have a considered plan for how you want to go about this. Particularly, if the control system for the ATC is provided by the KT510 (probable), replacing with a generic motion controller is unlikely to offer an out-the-box solution.

Having said that - I know nothing of the ATC on that Lathe.