What are you thinking about?

[UltraBudgie]

This is where they install the "stuff":

With the vast majority of the action hidden from prying eyes, perhaps it’s to be expected that most enthusiasts are unfamiliar with the fact that the Blue Oval has been digging into the Missouri bedrock for 70 years. You don’t have to be a Bond villain to appreciate the privacy, convenience, and stability of the caves

https://www.hagerty.com/media/automotive...city-cave/