OS 10.4 - Major Shortname/Admin/User Problem

Question

I've never quite screwed anything up this bad before. For now, let's try not to concentrate on WHY I did these things... just that they're already done... and I severely regret them.
This is my work computer, which also holds many personal files.
I am running 10.4.11 on a G5 PowerPC
There was only ever one user account on the machine.
I went to change the short name using Netinfo Manager.
I changed the "name" and "home" to reflect the changes I wanted.
For the sake of this example, let's say the original name was "WORK" and I changed it to "Coz". So, "home" is now labeled as "/Users/Coz"
This of course wiped out the profile I've been using all along, created what appears to be a new Home account by the name of "Coz" and no other user can be selected at startup. In Preferences/Accounts, there's only this one -- and it's a Standard User. I have no admin rights because there appears to not be an admin password/name anymore.
But...
I can see my old files and everything still exist in the directory "/Users/WORK" -- yay. they're where they're supposed to be.
I just need to get WORK to be considered the home account again and make sure it's got admin rights. But that's hard to do when no one has admin rights at the moment.
Puhleez. Help.

Answer 1

Ive looked at most of these before - and they all seem to not quite be helpful enough, or too confusing to make sense of. Or, the suggestion didn't work for me. I'll look through again, though.
_edit: after looking through, here's why these suggestions cannot help me:
+How to change user short name or home directory name+
+http://support.apple.com/kb/HT1428?viewlocale=en_US+
*Doesn't apply. It's already changed, I need to change it back... but I need admin rights. I did try the command "chown -R NEWNAME /Users/NEWNAME" but that didn't seem to do anything at all.*
+Also, this might be useful:+
+http://www.macworld.com/article/132693/2008/03/changeshortusername.html+
*Attempted to use ChangeShortName app but cannot without admin rights.*
+Apparent 'Loss' of Home Folder:+
+http://docs.info.apple.com/article.html?artnum=107854+
*Home folder isn't lost, it's just set for a new user.*
+Changing or resetting an account password+
+http://support.apple.com/kb/HT1274?viewlocale=en_US+
*Can be done, but doesn't help me any.*
+Changing your administrator password+
+http://docs.info.apple.com/article.html?path=Mac/10.4/en/mh655.html+
*You must know the current password. Or, if not, reset it using boot disc.*
*But this doesn't help because there is no admin-user to reset the password for.*