Pulled the plug out and it's dark and oily, so I'm sure it wasn't too lean. Using 50:1 regular 2c oil for now. Gotta get that tach working so I can tune it with confidence. Man, if there's even more power left in this beast - I'll be taking a wild ride.

Also, after a few days being wet, I was fooling with the choke and can visibly see the fuel (well, tiny bubbles) moving thru the line when I pull the prop - so it looks like the diaphragm was just a little stiff. Thanks for the advice, rcign.