Well, its together and running. I never really solved this problem. It will idle down just fine and it will rev up to higher rpms. But it will also try to overspeed and even will surge if the throttle "down" too far (yes down),
I read the referenced links but there seem to be quite a few variations on this carb. This phrase came closest to the issue:
"Fuel for the low-speed circuit comes through the bowl nut side hole, through this hole, continues past the Welch plug in #10 and on to the progression holes in #17. When this hole is clogged the engine might not run at low speed and may surge at high speed. Shooting carb cleaner into the hole from which the low-speed jet was removed should result in a stream squirting out this hole. "
The engine still only runs if the bottom high speed jet is screwed all the way in. (even with the rebuild kit and the float adjusted).
IU agree that swapping out another carb would be the best diagnosis.