The mill and lathe have the same axes as shown in the attached picture, except a lathe doesn't use Y. Lathe g-code would not have Y either, so you would need to add a Y move at the start to set the tool height. This should not change until the part is done. Then Y may be changed to clear the part so the machine can move to the parked position. Tool changes would need Y code added too. Other than that lathe CAM should be pretty close.
Also the Z plus direction should match both lathe and mill. The X plus direction may not match since lathes have front or rear tool modes. A lathe can also have a diameter mode, which you won't have, so think in radii.
Attachment 260880