I saved those old handlebars a little while ago, and always intended to make them into bullhorn handlebars that I could use as an alternative to regular ones. Let's do this.
First, take everything apart, and keep only the bars and the stem.
Clean those with steel wool until they look like new.
Mark the handlebars on both sides with electrical tape where you want to make the cut. Measure to make sure each side is the same. Cut with a pipe cutter or a hacksaw. File the ends.
Put it back together, and add a brake if necessary.
I didn't know what to expect but those are very comfortable and easy on the wrists. Love 'em!