The #21 David Pearson set records with has a 429 and is in the Darlington museum... is restored, and looks beautiful. This 351 Merc is likely a tribute car of a fans from the 70's. It was at the Auto Club 500 very recently http://www.rowdy.com/content/profile/blog/29050/auto-club-500-pt-2-raceday-pics
Pearson drove from 1960 through 1986, winning three championships despite rarely running a full Cup schedule. With 105 career victories and 113 poles, only Richard Petty -- who made many more starts -- ranks ahead of him in either category.