If you keep up with various retro vacuum tube projects, you probably have run across [UsagiElectric] aka [David]’s various PCBs that he makes on his own Bridgeport EZ-Track 3-axis milling ...
Figure 2-6: Simulation of a dual rotary mechanism fastened to the table of a standard 3-axis CNC milling machine. Tool length offsets work the same way here as with any conventional 3-axis machine.