Front wheel skirts- why not just put a motorcycle styled fender that covers almost the entire wheel/tire. The cover could be mounted into where the hub attaches to the spindle.
I have a quick drawing of how it would mount to the spindle:
This motorcycle fender would have to be quite light also.
I have a question, has anyone had success with a rear body diffuser? From what I have seen, it looks like it would smooth out the air at the back of the car.