I didn’t want the cabin heat to simply dump into the cabin without the ability to direct it via Scat tubing. Our Cessna 172 simply dumps the heat into the cabin near my feet and in the winter my feet are way too hot. The standard TG-10 heat control as supplied by Vans has a cabin side control and cannot be connected to tubing inside the cabin. I modified a Plane Innovations HBV-01 inside plate by cutting it to clear the support on the cabin side of the firewall. I drilled holes in the plate and dimpled the holes for #8 screws.