Our new 1983 300D ("Ben" 140,000 miles old automatic) is having a rattling noise emanating from below the gear shifter.
At first I just assumed it was something in or under the ashtray as I was in the process of repairing the radio, but now that that job is complete it is apparent that the noise is coming from the transmission directly under the shifter.

The ratting noise rises and falls with acceleration.
Has anyone had this problem? What can it be?