Their dad died and left this numbers-matching 1970 Road Runner convertible with a 440 Six-Barrel, four-speed, with a build sheet and 82,000 miles to his kids, who didn't want it, so they sold it to a repair and restoration shop

Plymouth made only 658 convertible Road Runners in 1970. Just 34 had the 440-6BBL engine, 14 with automatic transmissions, 20 with four-speeds.

This car’s history has been lost to time. The car was bought in New Jersey in 1973 and not long after moved to Chino in Southern California.

The last year it was registered was 1985. It sat outside for decades before going into a garage when the family moved to a newer home.

http://www.hotrod.com/articles/stored-30-years-garage-find-1970-plymouth-road-runner-4406-convertible-diamond-rough/