Not sure if this would work, but you could go to your Profile, click on "Settings", then click onto "Edit Profile".
From there, I believe you can change your "First Name" which states... *Required & VIEWABLE - This item will be visible by other message board members who view your profile. You may change it or choose to allow only friends to see it by editing your profile.
Once done, you would scroll down to the bottom of that page and click "Save Changes".
It should work, but I didn't try it myself. Let us know if does. Good luck!