I would imagine any metal shop could make them easily, or you could buy one for a stang and modify it. Personally, Mine is one of Geno's ice boxes. I do know the shield makes a temperature difference when the car is standing still. I have used a laser thermometer. I dont remember the specifics but the temp is a bit lower. I assume it gets lower yet when the car is moving. Another reason, I believe, to shield it, is to help control air flow. The air is more calm beyond the shield, thus its easier to suck that air into the filter. Outside the filter you have alot of air movement from the fan, air being pushed through the radiator, etc..