Vision is perfect
Nope, your eyes are still good. You have to use deduction based on other measurements given in the drawing. That floating line at the highest measurement is it, but it references another invisible point to measure from. Sorry, but I can't remember exactly what I did to figure this one out, but I know it involved a good bit of subtraction / addition to finally get the right measurement. If I remember correctly, it basically came down to some measurement off the tooling holes. This was a big head-scratcher, but it came out perfect.
