68 chevelle steering column problem

ever since i owned my 68 the steering column and wheel pulls out about an inch. if i pull on the steering wheel it will come out and go back in, it dosent affect the steering its just really annoying. ive asked around and noone seems to know, it has a three on the tree that was disconected for a 4 speed. its not the rag joint, the entire steering shaft pulls with the steering wheel. from the wheel to the box. ive had it apart and cant figure out what im missing, or what the shaft is missing? any thoughts would be greatly appreciated.