My advice was to have an adventure, and get a booth at some big event, like the car events at Hershey, or the Los Angeles Roadster Show Fathers Day swap meet in Pomona, or any of the Goodguys car shows.
Or get all those parts into an auction with some big or small company that takes a 10 percent or so cut, but they do the advertising, and have a built in repeat clientele, such as Barrett Jackson, (or my favorite) Morphy, or the incredible Van Der Brink.
Or go partners with some fun people like your nearby car club of choice, charity of choice, or people you want to inspire (boy or girl scouts) or just give it all to the person or car club who is restoring that type of car those parts go on.
Or ask any collector of 50's General Motors cars what they think all her NOS parts are worth. The more people you ask, the better chance you'll talk to the right person with a fantastic amount of experience, advice, or the right knowledge.
firstname.lastname@example.org if you can advise her on the best way to go about selling these