steering coupling??????

Hi everyone! My name is Carl and I'm in a bind and need some help! I just installed a floor shift column in my 72 dart. I have manual steering as well. The column did not come with a steering coupling. So I found a coupling and rebuild kit and rebuilt the coupling. My problem is I can't get the steering shaft to slide down to the bottom of the coupling. I just about have it seated on the splines of the steering box and the parts on the inside of the coupling are at the top of the coupling. Without destroying the steering column, what is the best way to fully seat the column into the coupling????? Thanks for any and all advice:)