Like this? go to "Fabrics" then "Grille Metal" pages on their site for the details.

 

Check out my gallery to see the screen I made for my cowl induction hood. Basically two pieces of metal with double ended threaded spacers to keep them apart. The piece nearest the engine bay has two slots in it, the outer one stops the rain getting in. The center support has a hole drilled through it and lines up with a hole in the hood, this is the only fastener.It´s a bit of a chore making the metal fit the cowl shape, you get through a load of cardboard.From the drivers view it looks like it´s blanked off, especially as it is now painted black.

 

HEY PRO:

McMaster-Carr Supply Company in Cleveland , Ohio sell all types of perforated metals. cle.sales@mcmasters.com DAVE

 

Best search term would be "perforated metal"

Here are a couple of the top...

http://www.marcospecialtysteel.com/perforatedmetal.htm

http://www.accurateperforating.com/

Google that term and you will have more than you know what to do with.

 

I did mine the way I did because when idling in traffic hot smelly air tends to come in through the heater. Only when the car is moving does the cowl induction effect start to work.