Rebuilding a 53 Bel Air suspension question

I am rebuilding the front suspension of a 53 Bel Air. Got the rebuild kit from Kanter and started the rebuild.

When installing the upper inner control arm shafts they went through the front easy and will not start threading on the back bushing.

Is this a sign that I need new bushing or do I need something to help force the threads to start?

I am installing the .008 smaller side first from the front.