I am the one with the B that would only run with partial choke.
I cleaned the heck out of the carb - no change. Upon the advise of a VERY good mechanic, I took the air/fuel adjusting ( high speed) and the jet inside. Drilled the jet out to 1/16th" and put it back together. Runs like a watch with no choke.
My clutch ended up only needing the rod exended ( adjusted ) and now it disengages just fine.
Not touchin nothin' else tonight - I'm 2 for 2 !!!!