Scott, just looking at it, I can see what you mean. On a more traditional mill, you usually have a way to raise the table toward the cutter. On this one you would have to build some sort of elevating platform to raise the work piece, which would be difficult to do accurately, and I'm still not sure how good the results are gonna be. If you're milling very narrow flats it might be viable, but I think this would turn out to be a lot of work getting setup in the first place, and may still be alot of refixturing since I dont think that table has much Y (assuming facing it from the lathe orientation is correct) travel.
If you're looking at a full sized surface grinder like a 6x18, I'm guessing that's going to be a lot more effective and efficient. You'll just have to figure out some ways to support the parts of the blades that aren't inside the working envelope most likely, and work in sections.
Face milling is usually a pretty machine intensive task requiring more HP and rigidity to swing a bigger cutter and handle the large cuts. Sorry, if I got you sidetracked here, but I think that mill might be great for slotting guards, but probably can't handle what we're looking at for this op.