I contacted the seller and asked for a photo of the Chrysler unit. His reply was:
The black assembly in the listing is actually the correct design for the Packard and Chrysler.
Regards, Dave
My reply to his answer:
Dave,
Thank you for your reply but your information is not correct. The Chrysler Letter Car examples for both 1955 and 1956 has four indented ribs running fore and aft. As per Chrysler historical records they did not use the term Batwing but DeltaWing to describe this filter.
JL
So here is yet another example of what happens when people don't do their home work.
John Lazenby (Stickler)