Why did I lean the low end? Slow sloppy transition from idle to half throttle.
Why did I lean the high end? Burbling at full throttle that cleaned up only during a vertical.
Why did the transition change? I'm guessing a greater air to fuel ratio, leaner mixture, which did not load up the cylinder like the previous setting.
The motor was obviously running rich without the cowl on. BME instructions recommend turning the needles 1/16 of a turn at a time (22.5 deg), my adjustment was 2-3 degrees.
After adjustments the transition was good and full throttle was strong without sagging. After 4-5 min. the motor got hot and quit during a low-mid throttle transition. After a couple of minutes the cylinder temps were 205 & 185 leading me to think that in addition to extra cooling, I needed to richen the low end.
Yes, I obviously made too many adjustments which is why I asked the questions in the first place.
Dick & Silver Surfer thank you for answering my question, as usual you have been very helpful.

Chris