Yes, the shutter assembly drawings for 30 and 31 seem to be missing. But there are enough surviving orginal cars and some factory literature to go by.
For Series 14 the hood front shutters are painted black as standard. Yes, some cars had black fenders, but black fenders or not, the shutters were black. Some shutters are painted body color or fender, like yours and the Marion Davies 30 Pursuit that are known to be restored, but that color many not be as it was when the car left the factory ????? Verifying that would take researching back to before they were restored.
Remember that the hood front was to have the cars look like the cars with water cooled engines. There is a service bulletin later on in '30 about the factory starting to paint the center bar black also, and it goes into detail how to do it to earlier '30s.. You see that on some original '30s.
Paul