I'm installing my rack, but I cannot seem to get the spline'd pinion all of the way into the collar. The spline on the Pinion, goes bout 1/2 way and will go no further. Is the collar keyed? Or perhaps I am missing something? It's currently on jack stands. I was wondering if perhaps being on stands is causing the issue.

you can always trust a dishonest man to be dishonest, honestly, its the honest ones you need to look out for. you never know when they will do something..stupid