I'm going to show my incredible stupidity here but under the dash on my '66, just over my left leg is a--for lack of a better description--"can" that extends down from what looks like the cowl. This "can" is about 6 inches long and four inches in diameter. It is open on the end, although it looks like at one time it may have had some kind of door or vent on the end--and looks like it dumps directly from the cowl area. Is this a vent opening for fresh air? What keeps water from running down the cowl and dumping on my feet?