These clips were used to attach hood latch release cable to the body support brace in front of the radiator core support. Pictures are from my 1978 Pontiac Firebird and my assembly manual shows this being the correct part up through 1981 firebird models.  Correct for many other 70s and 80s GM, Chevrolet, Oldsmobile, Buick, and Pontiac models as well. Use the GM part number 3979975 to cross reference in your parts manual, assembly manuals, and body manuals.