I am about to reinstall an old General Electric "Air Wall" register. On the back side, there is a strip of metal running around the inside of the perimeter of the register. It is about 1/4" from the edge of the register and is attached by what appears to be two heavy duty staples at the bottom and caulk between the strip and the register. The caulk is crumbling and missing in places.
Is that caulk that I am actually seeing, what is its purpose, and can I dig out the old stuff and replace it with new acrylic or silicone caulk? The register matches those in the rest of the house so I would rather not replace it. I understand that the design dates back to the 1950s. My house was built in the 1960s.
Thanks in Advance.