[Christ]

That's Ok, your answer is basically what I was after.

I'm not worried about tearing away, mostly because I would assume a real boat-tail design would be attached in such a way that it could not.

I think the effect I'm looking for data on is "Wind Vane" effects, where the rear tires become an axis if enough leverage is generated against them sufficient to (please read entirely) significantly lift the front tires in a cross wind situation at speed.

I am not suggesting that aerodynamic lift is or will be an issue! (Good gods, we don't need that again.)

What I'm suggesting is that because the wind is constantly changing direction, a well-aimed gust could be sufficient to force the tail down, creating a fulcrum of the rear wheels, while the gust force spun the car so that it faced into the wind.

Again, I don't see this as being an issue, I just want the data!

EDIT: Length is the primary consideration here, actually.. Weight only plays a small part in it, when considering the force necessary to be exerted on the structure as a whole in order to lift the front tires enough to allow the vehicle to spin laterally.