The coupler is fine. The car only has 58K original miles on it.

I had the car up in the air Wednesday so while I was under there I checked the torque on all the bolts/nuts holding the suspension together including the sterring gear shich I torqued to 80 ft.lb per my 1968 service manual. Also while i was under there I greased the ball joints and tie rod ends. I did something right becuase the cluck seems to have gone away.