U Joint 3/4" to 1"

[Goinlow64]

I have a new helix steering column with a 1"DD on the end of it. The setup I have on my power steering gear box is 3/4" DD. The 3/4" DD shaft fits in the steering column with no movement or wiggle room. It is a good tight fit.

My question is: Do i need to put a U-Joint on the end of the column to the shaft? OR can I just put the DD shaft in the steering column. The shaft goes in the column over 10" if I want it to. If I can do that, do I need to put a bolt through the shaft in the column or anything like that?

I am new to rebuilding trucks and post some basic questions a lot, but i really appreciate the help from the board!
Thanks!