I have an (Australian) Adept CIM system. This has an overhead mill with an XY table below it, and also a lathe head at the side. The XY table is used as the lathe tool holder for turning. Normally you would not try to run both spindles at once, and as far as I can tell Mach3Mill won't allow this either.

However, I want to put a workpiece on the table, mill parts of it, then use the lathe as a drill holder to bore out a long hole down the middle of the piece - as a boring machine. Doing it this way means I do NOT have the alignment problems you would expect if the workpiece was removed and replaced rotated 90 degrees so as to use the mill head for the boring. Yes, it does mean that the workpiece has to be placed at the right height above the table at the start, but that I can do (and being out in height by 0.2 mm doesn't matter anyhow).

Has anyone managed to do this?
Will it require a custom screen?
Should I treat the lathe spindle as another mill head instead? If so, how?

Any advice or hints (or help)?
(I have many years experience using a lathe and a mill, but CNC is new to me.)

Cheers