Not to 'jack the thread, but since I opened the can I dont want anyone following this to be confused or misunderstand.......on the mill 'as a lathe', you dont turn the head, but leave as is, as a verticle mill. Just visualize what your mill would look like laying on it's back so the headstock is horizontal, though.
You jig up a toolpost to mount on the table, holding a lathe tool properly to the work (which, like this is 'sideways') and advance via the table into the chuck held work to reduce the dia.. Then lower the spindle to 'cut up the stock'.
For filing, polishing, etc. longer stock you can actually hold the work in the chuck and to a center mounted inline on the table (then dont move the table adj.).
Like I said, its a little goofy to think about, but I have done it (even though I have 2 lathes also) just because 'inquiring minds want to know'. So if anybody wants to pursue this and has questions, PM me!