The height setting tool for dad's lathe is a block of HRS, approximately 2" wide, 1" thick and some 7.4883" long. I just match up the height by raising the adjusting nut on the QCTP holder until I can't catch my fingernail running from the top of the block to the tip of the insert. Simple, and completely non-adjustable....just like the center height of the spindle on the lathe.
Nice job coal miner it looks awesome. Paddy could you take a picture of your height setting tool and post? It's wild how so many different ideas are dreamed up.