In the following thread: http://www.lawnsite.com/showthread.php?t=75521 there is mention of upgrading the Stihl FS80 trimmer to an FS85 by installing a solid shaft. Then other attachments can be used. I called my local Stihl dealer, and they had not heard about doing this. Can anyone provide details on how to do this, or what Stihl parts are needed. Thanks.