Harbor Freight Mill Lathe | Smokstak® Antique Engine Community
Since you say it's a mill/lathe combo, I would assume that the spindle taper refers to the lathe spindle. #3 Morse is very likely the taper if you were installing a center for turning between centers. It sucks if the mill spindle is #2 Morse taper. That's fine for a drill press, but really limits your options on a milling head.