Thanks very much for the link.
Without modern computers and programs to aid in the prediction of resonance, it’s quite amazing that they did this with what they had.
On a much smaller scale, I worked for a company in the 80’s that kept having broken circuit boards in shipment. This was a high-power piece of equipment with many heavy semiconductor packages. Our new hotshot packaging guy built a model of the unit on a computer, and he discovered that the board had the same resonant frequency as a semi truck on the road - he made an animation of this (which took all day to render). The fix was a $0.20 spacer and post, and the problem never happened again, period. Our marketing department would show this animation to prospective customers as an example on our abilities to solve problems.