The part that moves when you move the stop control (where the stop cable attaches to the governor) is the "fuel shut off", it pulls the rack back to the "no fuel" position when you pull the engine stop control. The fact that the stop control is moving inside the governor doesn't mean that the rack is moving. The rack is the part that is connected to the governor and runs all the way along the inside of the pump next to the plungers. The rack has teeth on it that engage with the teeth on the plungers and when the rack moves toward the front of the pump this turns the plungers to increase the amount of fuel delivered to the injectors, or if the rack moves to the rear it decreases the amount of fuel. When the stop control is pulled it pulls the rack all the way to the rear, preventing the plungers from sending any fuel to the injectors, thereby stopping the engine. As I said before, since the rack teeth are engaged with all 6 plungers, if even 1 plunger can't turn, then the rack can't move and none of the plungers can turn. I personally enjoy solving these kind of problems, and if I was closer to your area I'd be there helping right now, but 1000 miles is a bit far.