When I made the bandsaw work holding gadget recently I needed to machine V slots and spent quite some time thinking about how to secure the work at 45 degrees so I didn't have to move the milling machine head. In the end I gave up as any arrangement I came up with was not safe enough for machining the V slots. Setting over the mill head made the operation very easy and safe.
Now for the tramming to bring the head back to the vertical. I had made one of the Bogg's type of tramming indicators and using it made the whole operation so easy that I should not have wasted all that time trying to avoid changing the angle of the mill head.
So here is a big thank you to all the folk who post such useful ideas.
John