Steering U Joint Questions

Rob, as much as you dont want to, i would tack weld it. The hollow tube will distort and wear if you use a through bolt.
Two set screws 90 degrees from each other is the next best to welding. Unless you press a rod inside tube to make it solid. No more horn wire though. Need a support bearing above the u-joint in the tube, you already know that.
My next project is getting a different column. Tilt wheel. Yup.