Hey Wookie, Just spent the afternoon on my front brake, the caliber is working perfect. I understand your thinking on 14 mm vs, 5/8, I'm there too! But everything is simple on the 74 single disc. I installed all new Japan manufactured OEM replacement parts, including hoses and distribution block. I loosened the two bolts holding the caliper, grabbed the brake and the lever moved almost full pull the tightened up, retorqued the bolts and it feed build back into the reservoir and tighten right up. I did this multiple times and it repeated. So matter what gap there is between the puck, the master and caliper does exactly what it's supposed to do. When I release the brake lever, wheel is free, so no dragging brakes. Actually it's a total of 1 inch pull for brake handle for a firm grip. Other than the distribution block, there nothing left in the system. I've worked on my own bikes for as long as I've been riding, 50 years now. I've had normal brake issues on bikes and cars but never ran into this. That's why I like forums! As much money as I've put into my Z1, a few more bucks isn't much to try to resolve the problem, especially brakes. I thought of the two disc conversion, buck that's a hefty price, but prefer to keep it stock as much as possible.
Thanks, Guys!