Looking at the rear of the F6b pic, behind the seat. It looks like there is a "cap" that could cover any connectors once the trunk is removed. If it was not covering something, it could have been flatter. Just being optimistic.
I read that the F6b model shield all the way down is 12" shorter than the Wing shield all the way up. Looking at the pictures and doing a little math, I am guessing that there is 4" of windshield adjustment (on both bikes) and that the F6b shield is 4" shorter than the Wing shield (did I do that right?).
Of course, all this is speculation, but fun!