Frame and Springs.

On 1947 Commander Convertibles, there is a listing in the CHASSIS PARTS book for a Harmonic Balancer/Vibration Damper that is supposed to mount on the frame. It is a series of heavy metal weights, joined together by
plates.
A) Nobody I have talked to, has any idea where or what it is.
B) The drawings are ambiguous, and parts sellers have never heard of the part numbers.
So what is it, what does it do, and do I need it?

Answer:

        Most convertibles have them, they are there to dampen out "cowl shake" or vibration due to the lack of body stiffness caused by the lack of a steel roof.