Originally Posted by GearNut
Pulling the choke enrichens the fuel/ air ratio so your assessment of too lean is spot on (if I am reading what you said correctly). If you are referring to applying the choke all the way and the engine runs poorly that seems normal, the choke is only there to aid in starting when the engine is stone cold. To help diagnose what the carb needs for tuning, try partial choke settings in small increments instead to see if there is any improvement. If there is than you are too lean, if it is worse you are too rich.
As for the issues at full throttle, definitely do a plug chop at full throttle to be sure.
(Don't forget to let the engine cool down completely before removing the spark plug.)
Lowering the clip on the slide needle will raise the needle and enrichen the ratio up to 3/4 throttle. If you are having issues above 3/4 to full throttle that indicates that the fuel jet is too small.
Thanks for the help, any choke at any setting kills the engine.
The major problem has been at WOT, so re-jetting is the answer.