The Horizone one looks nice. Does it work on an old style flywheel?

However I have a bar of aluminum, a good lathe, and a couple of beers that all need attention. Fortunatly my 3-jaw is within a thousandth of being dead on. It looks like the horizon hub would fit over a nut that holds the flywheel in place. The "nut" would have a cylindrical section that pilots the hub to be dead center. Foreward of the pilot bore there are threads to secure the prop bolt? The two cap screws only serve to hold it on? I have never taken a "new" style G38 apart so, I can only guess.

That seems convaluted to me. Also the flywheel face needs the be true to the axis of the line of the crank. That is a big 'IF" IMHO. So, to do this right I need to true the flywheel face, in the lathe, with the flywheel on the crank. Hopefully the two holes in the flywheel that will be treaded for the cap screws need to be in the right places.