Thanks much. I agree on the spoiler thing. That is why I have not put one on yet. The duck tail type is called a Kamm Back, named after a German guy who discovered the reduced turbulence that resulted from this design. Many, many new cars incorporated this design into the basic body work. So far I have not figured out how to add one without seriously changing the appearance or basic lines of the car. I have been looking for a stock item that could be adapted to the Dart. The closest I have seen is the BMW 6 series from the 80's. I have almost bought one of these cars several times. Scroll down a ways on this web page to see several with the factory spoiler applied to a very similar shaped car.
http://forums.bimmerforums.com/forum/sh ... Your-Shark!
Last night I added the final touch to the front lower pan, and that is the tab that sticks down in front of the wheels. I will post a photo soon. I used a standard plastic kitchen trash can for material. I cut the bottom off about 3 inches up, and split this, turned it over and screwed it to the bottom of the pan more or less in front of the wheel. Like the airdam it sits a little inboard of what would be ideal. I see only the corner of it from a normal viewing angle.
Sam