[firebones]

First thing to note is that while the pictures are from the 1960s, the article merely says that Ford uses (and has used, for years) these caves to store cars in transit.

The Kansas City Ford plant manufactures more trucks/vans in a day than it can ship to their destinations, and Ford uses almost any surface lot it can rent (including a nearby amusement park's lot in the offseason) to hold cars until they can be transferred by rail or truck--it's very demand-driven. It's completely natural they'd use these caves as well based on their proximity to the rail and interstate transport near the river.

I don't see in the article anything that implies there's a cache of 1960s cars down there gathering limestone dust. That space would quickly be reclaimed for temporary storage of Transit vans awaiting their buyers.

[WalterBright]

The article didn't say the picture was from the 60's. But that would answer my question. I thought it would be quite a treasure trove for collectors!