Ben, Louis, and anyone else interested,
in my opinion, the low wind deflector I made works "well enough". With the screen down, if I wear a baseball cap the wind buffeting in the cockpit will blow the cap off at highway speeds. With the screen up, the cap stays on. However, not all wind is eliminated, which I like. By shear luck, this design is what I'd consider a nice compromise between too much wind and not enough. My wife and I made a 1200 mile freeway trip top down all the way, and we both thought it worked well. I'd guess the taller screens reduce the wind even more.
I don't have actual plans, but will make some measurements and take some pics of details and post here; it'll probably be a few days before I can do that.
George Davis
'69 280 SL Euro manual