Answer:
its not four but according to lists from somewhere these were the most popular cars in the 1960's
Ford Bronco.
Ford Thunderbird.
Buick Riviera.
Pontiac GTO.
Lincoln Continental.
Jeep Wagoneer.
Dodge Charger.
Cadillac Eldorado.
etc.
-1960 Austin Mini
-1961 Jaguar XK-E
-1963 Chevrolet Corvette Sting Ray
-1965 Ford Mustang
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