The part might not have been installed in your car for various reasons. BTW, your work looks good!!Interesting. I've owned this car since 79'. My brother bought it used in 76'. I know I didn't remove anything like that nor him either. Thanks for the reply and the picture.
My '71 charger SE had one. 383 HP, 727 column auto. I did not put it back in. I saw a '73 Rallye charger, 440, column 727 on a lift and it had one. First thought I had was vibration control.
That's likely the case. The car was dipped so all the sealer was removed. I wouldn't have known there were holes there. ThanksMy 71 has one but my 74 did not come with one, the holes are just covered with seam sealer.