Hydrogen generators with three carborators

by john jaynes
(long beach,ca.usa.)

I have a 175 Yahama out board i am installing a Hydrogen generator on it, do I have to feed each carburetor independently, or can I put it in a common air-cleaner.
The carburetors are in vertical formation so if I put it in the bottom of air cleaner will the bottom carburetor get all the hydrogen, or if I put it in the middle will the same thing happen with the middle carburetor, same thing at the top.

Or should I feed each carburetor independently? Were looking at 18" of vertical air-cleaner. Can really use some help here!!!!!! John.Long beach cal.