Just to add here, the 55-56 car air cleaners were a clamp type cleaner and the carbs for those motors did not have the cross bar and stud arrangement that the 57 and later carbs did. In 57, the pass car had a lower hood profile then did the 55-56 so instead of the clamp on the air cleaner, there is a recessed area on the top of the cleaner for a stud and wing nut and the carb has a cross bar for a stud. This set up helped get the lower profile hood to fit.
