where do these mount?? wind diffusers?

hi all,
I got these cheese graters from a buddy. I'm not sure how they mount though. I believe they are wind diffusers that are supposed to go on the pop out windows in front. BTW its for a 54 chevy.
Any help is appreciated. Thanks.

 

They look like the sort of things the lowrider guys might use. Check a few lowrider sites

 

I think they go on the leading edge of the doors, and not necessarily the vent windows. I had a set just like them. I never really understood their purpose, but they're neat looking.

 

They mount at the leading edge of the door, they reduce wind noise and help to lesson the amount of wind coming in the window.

 

Those were to keep rear window clean on a station wagon.

 

thanks guys.
I like the fish board suggestion.

 

Great to keep the kids from getting burned on the minibike exhaust too!

 

I would mount them on the hood

 

I think they go on either side of a semi truck exhaust stack

 

HA! That's the first thing that came to my mind too