Well, I didn't make
it to that shindig, didn't know of it until today tbh, but it sure looks like it was the place to be on a non F1 race weekend. Racing legends to rub elbows with, classic racing cars and whatnot, all to the setting of scenic Newport and Aquidneck Islands and the property of one of the wealthiest families in the US.
Here are some links, note the links bar on the left in the first one, it's a little less than obvious.
Concours d'Elegance
Gordon Kirby's article, featuring Moss and Gurney
Stirling Moss
Dan Gurney's All American Racers