You have to remove this like you would remove a riveted on ball join. You drill a hole through the middle with something like a 3/16 or a 1/4" diameter drill and take a cold chisel and chop off the rivet head.
This is a "tamper proof" installation on the later cars. Earlier cars has "one way screws".
You can probably step up the size of the drill bit also until the head falls off.
As I rember, the heads are hinda' thick. Take the entire column out and do it in a vise on the bench.
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