I had this problem and I've decided that the guide for removing and replacing the click wheel is not 100% correct. In actual fact, the metal bracket around the connector port at the bottom of the iPod also helps hold in the bottom edge of the click wheel. So, the correct way to remove the click wheel is to first remove the bottom plastic bit, then remove the 2 screws holding in the metal bracket surrounding the connector port (the middle and right screws at the bottom) and remove the metal bracket before attempting to remove and replace the click wheel itself. When you replace the clickwheel, you need to make sure that as you insert the metal bracket the clickwheel is properly in place so that the bracket holds in the bottom edge of the click wheel. Simply apply a little pressure on the bottom of the click wheel as you return the metal bracket into place.