Glassback Roof Install - Chrysler 300 Greenhouse Glasses

Our subject was an '08 300 with the latest style, multifunction roof antenna. This one didn't have a moon roof, but CDC's installers can even replace roofs so equipped.

Two of the kit's three major components are the 38x51-inch laminated glass panel-surrounded by a rubber trim seal-and the stainless steel roof cap onto which it bonds. In this shot, the mating surfaces of both parts have already been prepped with black adhesion promoter/primer that will ultimately help ensure the two parts become one.

The third major component is an interior item: a molded trim ring that will be covered in headliner material and used to trim out the interior circumference of the Glassback panel. But installation of that part is a ways off yet.

Surgery begins with the removal of the gutter trim molding. This flexible, body-color molding will be re-used, but needs to come out to facilitate fitting of the stainless roof cap.

CDC's installation shops employ reusable rubber templates to establish a cut-line for roof sheetmetal removal. The template, which is used to trace one side of the cut-out and then flipped over to do the other side, is positioned along the longitudinal centerline of the roof, a specific distance behind the front edge of the roof.

This looks brutal, doesn't it? An air chisel is used only to create an entry point for the electric shear that will be used to cut out the perimeter of the opening.

Initially, two separate fore and aft cutouts are made, separated by a transverse stiffening brace under the sheetmetal skin.

As the rear cutout was made on our subject 300, the roof-mounted antenna was removed and unplugged from its harness.

Here, half of the sheetmetal atop the roof stiffening brace has been removed. The black material on the brace is factory installed to keep the roof skin from vibrating against the brace. Notice that the car's headliner has been left intact at this point to keep any metal particles out of the interior.

The air chisel comes into play once again to separate the eight spot welds securing the stiffening brace. Those of you worried by the thought of removing a stiffening brace have to realize that it's really only there to support and keep the large central area of sheetmetal from fluttering at speed. The Glassback's laminated layers of safety glass are much more rigid than sheetmetal and do not need any bracing for stiffness. In fact, the Glassback has been tested and passes the government FMVSS 216 roof-crush test and, because of its increased thickness, is in all likelihood even quieter than the factory roof.

With the paint outside the gutters suitably protected, the next step is scuffing the remaining roof paint surface. This will help ensure the stainless cap will bond securely.

As on the areas where the glass panel will bond with the stainless cap, a primer and an adhesion promoter known as an activator-the black stuff-are brushed onto the scuffed roof sheetmetal where the cap will sit. This and the adhesive that will follow are the same materials used by the OEMs and aftermarket for bonding and weatherproofing windshields and backlights.