Hi Larry,
The engine has only had about 150 miles total on it, to date, since it was bored 0.060", new pistons, rings, babbet, etc. First time I ran it, it stalled out when applying the brakes. I found that the zenith carb had the cap jet and the idle jet reversed, as I remember. Also it had an air cleaner on it. Anyway, the thing had run awfully rich as the carbon indicated. Plugs are Champion W-14.
I re-torqued the studs twice after I acquired it, but after sitting over the winter, the head had blew/leaked water between cylinders 2 and 3 (as shown in the pictures). I forget now, but the gasket was a copper R2, if I remember correctly. The studs and nuts were not high grade. I put a machinist straight edge on the head and it was low in the center by 0.005-0.010".
I've since gone through the whole engine to make sure things are correctly done. Yes the tool just touched the center, and it looks like the machining will give it enough bite for the gasket. It's hard to see since the surface because of discoloration from sitting around and the metal prep I used on it before painting. I also will clean up the combustion chambers before reinstalling and I have higher grad chrome-moly studs and nuts.