I still haven't resolved the issues with the engine. Now I run it right on the edge of lean on the top end and lean on the bottom end to the point that it's a little harder to start. It still stumbles in the midrange but the throttle response from the bottom to top end is gradually getting better. I have close to twenty gallons through it now and it still gradually changes tune like it's breaking in. I plan on messing around with it quite a bit this winter when the snow flys. I want to spend more time messing around with header length.