I got too curious and had to check if it will run...

The piston to cylinder fit is very nice and it fired right up on a port prime. I then ran it very shortly and rich on 25% castor fuel, just to check what will happen. It does make some grey stuff but everything is new so that is not too surprising. Looking carefully around the disk afterwards I cannot see any galling yet, just the grooves from the lathe work. Only time will tell if they will polish out nicely, or if there will be a problem. Should be enough now for the occasional bench run at least. Here are a few pictures taken after the run (open them in a new window for a closer look);