1918-1921 Stutz Exhaust Cutout

[PMac]

Looking for some technical assistance please. My 1920 Roadster has a large (horse shoe shaped - see photo attached) exhaust cutout incorporated in the exhaust piping. Unfortunately there doesn't appear to be any mechanism to open or close the cutout flap. I note that similar 16 valve Stutz cars have a button on the floor, next to and similar in design to the starter button, that activates the cutout. I am hoping someone might be able to provide some photo's of their car and the mechanisms (levers and rods, etc?) that activate the exhaust cutout flap.  Any assistance would be very welcome. 

Thanks,

Peter