This panel was originally plastic and installed on the big block a/c cars. GM knew that air was being re-introduced to the front of the radiator when these cars idled. At speed the pressure from air coming under the core support was working against the flow of air through the radiator, so this panel was designed.
The GM panel only goes as far as the core support. We wanted to force ALL of the air from the grille through the radiator, so ours goes all the way up to the backside of the spoiler (or to the valance). It has a divider at the core support to finish off the seal.
They are very easy to install and remove for mechanical work. They are fabbed out of 14 ga aircraft aluminum and come with all attaching parts and a cobalt drill for the 2 holes at the large crossmember.
These panels are anodized with an architectural grade process so they won't fade.
