Your machine looks more like a machining center to me-
(XYZAC). Not a lathe. Am I mistaken?
I built a post for a machine like that, but it is in MDFG (GPM) which still works, but is considered legacy by NX standards.
I am building a post for a Lathe- with a spinning chuck in turning mode, that also serves as a C axis in milling mode.
D