[aerohead]

I'm in the,use solid material where your going to block,and leave open the areas your not going to block camp.The perforated metal shown,has no leading edge radii for the openings,and will result in what is known in fluid dynamics as high vena-contrata losses .Its virtually an aerodynamic abomination,a torture chamber,if you will, with regions of separated flow in either laminar or turbulent boundary layer conditions at each and every opening,and imparts the very drag your attempting to abate.Keep it simple.