I think I know what you’re referring to. There was also a gizmo that mounted to the seatpost to allow rear hanging. I have thought about looking for something like that, or fashioning something from hardware that could clamp to the quill. I have not come up with a decent idea though and I would rather not add more hardware if I don’t have to.
Thanks for the replies. I am encouraged. Those who have done this - did you just hammer away at it cold, or heat it?