String Trimmers

I have a Husqvarna 128LD that has worked great for several years. I need the extension attachment due to my height and constantly having to bend over when I use the trimmer. I am being told the extension only works with the LDX model, but several other attachments do work. Can I get the specifics on why it does not work with the LD model? Can I modify the trimmer or the extension to work with my LD? What can be done in order to operate the 128LD with the extension attachment?