So, with the dial indicator, it looks real similar to what we do along the main saddle for z depth, so, like you said, we're "used to" dealing with this type of setup to get our depths. But after reading your last post, I think the use of a HF vernier as the main measuring tool has many advantages, one being that I've seen them on sale (warranty included) for about $10.00. Plus, the actual range going from 1 to 6 inches is an obvious advantage. Then there's direction. Properly mounted and modified, it will read depth in the correct direction. Awesome idea, (maybe marketable?). If only manual lathes were as popular as they once were.