Hi I'm a newbie and I have read this thread and the other one that was recommended. (Thanks!!) When I got my 401a, the stitch selector knobs would push/pull as described in the manual but wouldn't turn. After oiling and using guidance in these threads, I had the outside knob (a-j) turning freely. I began working on the inner knob. It would pull out and I got some very slight movement. I would occasionally rest that knob and turn the a-j knob. I must not have gotten the a-J knob fully back in place (I've realized by reading here), before I pulled on that inner knob to move right side... Because both knobs are jammed. I can't push/pull either and no movement. Have I hopelessly jammed things? I ordered tri-flow but for now have put oil in all the described places. Any advice is so appreciated or guidance to another thread. Thanks.