In the second pic above you can see the three machine screws, then look inside the column and you'll see the big ring with the three holes in it. There should be three springs over those screws then the screws get screwed into to the lower ring. Then, you install the complete assembly into the column. It can only fit one way as the lower "ring" is keyed to fit only one way. Then you rotate the assembly "locking" into place, then you tighten those three screws and it draws the cup down to the lower ring. Then you can get the snap ring back in place...