1976 was, in my opinion, Peak Brougham. It was the last year for the truly large premium sedans, the Cadillac Fleetwood, De Ville, Oldsmobile Ninety-Eight and Buick Electra. Over at Chrysler you had Royal Monacos, Gran Furys, New Yorker Broughams and even the wood-paneled Town & Country station wagon. And over at Ford, there were…