Has anyone done this? We all know the cambelt bonnet vent is blocked off on the cambelt cover from the factory and is largely pointless anyway, but a bit of airflow between the chargecooler and cam cover would be of great benefit in the war against unwanted heat soak. I was thinking about cutting the side of the small rubber duct on the engine, and making up some ducting to feed air under the CC. In addition adding a coarse wire gauze onto the vent exit on the underside of the bonnet would prevent any stray rain drops causing any problems to the plugs/leads, but the way in which the OEM ducting is designed I don't think this would be a problem anyway.
Even with my thick ThermoGuard lagging there is adequate space between the CC and head for this to be of some benefit.
It would be nice to put that little vent to some use