Now that we have root, I've been able to use this method to get tethering on my Atrix HD:
http://xdaforums.com/showthread.php?t=1160452
My line number was 107 but yours maybe different. Good luck!
http://xdaforums.com/showthread.php?t=1160452
My line number was 107 but yours maybe different. Good luck!