How many have a sealed air pan to their hood scoop? Is it worth the effort?

I have a glass hood with a 6-pack hood scoop. I have been measuring and sketching. I will have to put a panel on the bottom of the hood to reduce the area, and an air pan that is approximately 18" long and 20 inches wide that covers over the intake manifold.

The cooler air will always help, but i will get that with an unsealed scoop. Do you get much more HP from the "ram effect" with the sealed hood scoop?

Thanks for your inputs.

John