Verify that the cotter pin and control pin of which we speak was covered by
the torque converter cover.  (Removing that cover is the step just prior to
removing the shift cable. The attachment point of the shift cable is very
close to the gear teeth.  Can you see the gear teeth?)

Maybe you are labeling the entire bracket that connects to the shift cable
end piece the "control pin."  Upon close examination of the illustration in
the service manual I note that the cotter pin is the only thing holding the
control pin in place.  The cotter pin goes through the ears of the control
pin.  Once the cotter pin is removed, pull the control pin out and the shift
cable is free.

Loosen the top and bottom locknuts on the throttle control cable.

Press down on the throttle control lever with your left hand until it stops.

While pressing down on the throttle control lever pull on the throttle link
at the rear of the engine compartment with your right hand.

Remove all throttle control cable free play by gradually turning the top
locknut.  The control lever should begin to move at precisely the same time
as the throttle link.

When set tighten the bottom locknut and recheck the adjustment.  Verify that
the cable moves freely by operating the accelerator pedal.

(Honda technicians have an improved adjustment technique using a hydraulic
pressure gauge.)