Neil
The reason my tramming device is stood on three legs, is so it can sit on the mill table spanning the vice. The three legs are simply adjusted to the same length using a micrometer, that ensures the surface is truly parallel to the table.
I cannot claim any design rights on this tool, I saw this and realised I could make one in about half an hour.
http://www.eztram.com/what.asp
Nobby
The vertical head does have just over two inches of quill movement.
It is an Alexander Master Toolmaker, the UK equivalent of a Deckel FP1
http://www.lathes.co.uk/alexander/index.html
Phil