Now, just to be perfectly clear.....You are referring to the handles only, right? (I don't want to buy a round ball handle and then find out I need a different mechanism.)
In my post #7, I was not thinking of replacing the mechanism. I just wanted to make the point that the slip-in style mechanism was applicable to 68-71 A and B body cars. So, it should not matter whether the 2nd owner changed the mechanism or not, right?