1967 Dart GT 273 2bbl Convertible. I think the rad is a 2 core but the rear of the rad is flush with the mounting brkt and any additional rows would be forward. I am sure the rad has had the core replaced some time in the last 52 years.
Some of the photos make it look more like 4 1/2 but it is just camera angle.
From Radiator face to the front of the WP pulley between the fan spacer I get 4- 5/8 to 4 3/4