My situation is difficult to explain on the internet or phone but I'm going to try anyway.... I have a new bcz2450t trimmer and I am confused about the installation of a Oregon speed feed head. I probably made my life more difficult by completely disassembling the stock head in order to remove it but I am almost positive I am at the correct stage in the process to install the new head. There is a black bushing that rotates at the end of the shaft. Below the bushing is about a three inch "stud" that is threaded at about the last half inch. If I am approaching the installation correctly, one of the arbor (adapter) studs should screw into the new speed feed, which in turn threads into the matching arbor bushing and the arbor bushing simply screws into the half inch stud at the end of the trimmer. None of the arbor bushings will match the threaded stud on the trimmer. One of them seems to be the correct diameter but the threads will not line up. Am I missing something? Does the three inch piece below the black bushing come off? Anybody have any pics or suggestions? Something that seems so easy is about to drive me nuts!