carbking, trying to learn the points you mentioned

you wrote
"The third screw (the curb idle screw) is probably located in the throttle arm (the arm to which the linkage from the footfeet is attached). At some point in the travel of this screw, the throttle arm should begin to rotate. Turn the screw until you observe this rotation"

is this the screw that makes contact with the cam like part on the linkages? if so i see the screw contact points vary depending whether the choke is open or closed.
from which position should the adjustment you described be made

thanks