My 73 Challenger is that way. No lower bearing. Just the plastic piece at the bottom. I've heard that from the factory there used to be a foam seal inside the plastic piece. It kept hot air from traveling up the column and heating the interior.

On my 68 Dart, there was a lower bearing but it was seized. The factory replacement was expensive so I used an ER-16 bearing instead. Lots of people are using it.
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