Are you sure that you have all of the pieces for those brake levers?
There should be a ferule that goes in the hole in the top. The ferule holds the cable housing and the whole assembly is held in place by cable tension once you have the whole brake set up. An old, dusty bike shop will have a few of those ferules stashed away someplace. I'd expect them to be pretty cheap.
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My greatest fear is all of my kids standing around my coffin and talking about "how sensible" dad was.