I took the idler pulley of of my 1995 Crysler Cirrus to loosen the belt to replace the alternator. Now that I have everything done, I can not get the idler pulley to go back in straight. I can get the bolt in, but once you start to tighten it up, it shifts off-center. I can feel a part (like a nut) inside the area where the pulley came out of, but can not move it to where it (I assume) slides back and forth to create the tention. Could something be blocking it from moving? Or, am I just screwed? HELP. Please.