Here is a used factory air cleaner for 1972, 340 engine. It is in good condition, but could use some refreshing for show. I believe this may also fit the '73 340, also. There are a series of holes drilled through the bottom, outside the perimeter of the filter element, and I am not sure if they are factory, or some modification, but they do not show from the top.

Has the original factory 340 4 bbl decal, as shown in the pics. There is a flapper door on the bottom, operated by vacuum, to allow more fresh air in during low vacuum situations, and it has the heated air door arrangement, to preheat air to the carb for cold running and warmup. I am not sure if either of these work to specs!

Price does not include shipping!