Hedgehog,
Now wait a minute. Are you taking about the 'Economy' Heater? If so, that vent is only about an inch square. I think its purpose was to pull a snall amount of cabin air in. I might be missing something from the kick panel area though. The other owner pop-riveted fiberglass panels in. I can see part the the exterior louvers with mounting holes in the upper left/right corners of the inside cowl panel. My guess is the 'Fresh Air' Delux heater mounted there. :rolleyes:
