Nice Neal!
That's the exact same vintage as mine but maybe slightly smaller frame size (is it 22 1/2" or 23 1/2"?). One question ,though, why would you mount the fulcrum clip (cable stop) below the brazed-on tab on the down tube? Usually, one mounts it above so the cable stop doesn't slide down or shift while under load. Also, does your heel ever strike the cable? Using the Cable tunnel actually moves the cable closer to one's heel than if it were run through a S-A clamp-on pulley on the seat tube. Having long feet, I worry that this will be a problem for my own IGH project. Are these 27" or 700C wheels?