Ventilating a Boushh-Helmet?

Hi gang,

I am working on one of Todd's Boushh helmet kits at the moment (by the way: AWESOME KIT :cool) and since I want to make it wearable I toyed with the idea of adding a ventilation system to keep the lenses from fogging up.
Now the question is: Has this been done before? Is it even necessary or does the main-opening provide enough air draft already?

Where would you add the fan? I have been thinking the snout would be a good place (adding small holes to the mouth-piece or something like that).

Anyone out there who could enlighten me?

Have you thought about putting a small spacer on the bottom of the lense on the inside of the helmet so air gets in all along the bottom edge? It works in my TK and Imperial Gunner helmets.