On Barn Finds recently - maybe the most complete and solid 79 Grand Prix I have seen. From my recollection, the universal G-Body replacement door panels and consoles don't look like the ones in this GP, so this car in this condition may be "the one" for someone who wants an all original Grand Prix.
barnfinds.com

Way Out Interior! 1979 Pontiac Grand Prix
The Grand Prix was a fixture in Pontiac’s entourage from 1962 until 2008. The biggest change in design may have come in 1978 when General Motors downsized all its mid-sized automobiles, which included the Grand Prix. They were smaller and lighter, without giving up space for passengers and their...