He missed one detail; in the trunk there is a set of steel u-channels which form the support for the wing. Early test models without them would end up with wrinkles in the quarter panels from the 300+ pounds of downforce the wing would generate. The support ties the frame rails to the underside of the top of the quarter panel, where a large (12” x 24” approx) “washer” sat supporting the wing.
Interesting. I like how you could adjust the wing angle.