This picture shows the top detail. To assemble, slide the metal sleeve onto the Micarta tube (this is already in place in the photo). Make sure the notches line up with the holes in the Micarta tube. Then slide the top cap piece into the hollw tube, lining up the holes in it with the holes in the Micarta tube. Then slide the steel pin into the hole in the micarta tube, through the hole in the metal piece, finally coming to rest in the opposite hole in the tube. Finally, rotate the metal sleeve a quarter turn to "trap" the steel pin.

(You can see one of the asbestos washers in place up in the cap. I am not sure why they were painted blue, but they were.)