My mechanic buddy called in and loaned me a cooling system pressure checker which we figure will serve to check the pop off pressure of the fuel metering jet. He listened to it running while I was having difficulty getting it to take throttle without missing. He immediately suggested an ignition breakdown problem, which I agree. I was mistaking that for a fuel mixture problem all along. After we removed the spark plug, which looked a good colour, it measured .6 mm gap. Barry suggests to reduce that to around .4 mm and try that.
Order of events for the next session:
1. Do the pop off test.
2. If that test result is far out of parameters, adjust etc.
3. Change out ignition components as suggested by Av8tor above. I only have one hall sensor and I might have to order another one. Deliveries takes weeks etc.
4. Remove the engine from the plane and mount on the bench again. My old body is suffering from bending and squatting down to work on it in the plane.
5. If all the above unsuccessful, shelve the project until after our coming Manilla Slope flying festival in four weeks. I have a fleet of gliders to prepare etc.