[Donunder]

While I agree with Craig that force-fed air through a large diameter hose is the ideal way to go, I have 2" diameter pipes running from the brake air inlets, with the inlets fully covered by a funnel so that all air is directed into the pipes.

Originally the footwells became very hot in the summer. The pipes duct sufficient air so that the footwells are neither cold in winter nor hot in summer. It's a nice neutral feel down there now, with the piped air gently displacing any built-up hot air, rather than providing a forced blast. The system could be more effective with larger pipes I suppose but for an inexpensive solution to having scorched feet during Queensland's summer months, I'm happy with what I have.