Deinstall by deleting resistry keys

I have tried to deinstall my SQL Server Enterprise Evaluation Edition so I can reinstall my newly purchased Developer Edition License. I originally tried to upgrade, but the upgrade failed. Attempts to deinstall the from the Windows Add/Delete Programs ap
plet have also failed.
I followed the instructions at http://support.microsoft.com/?id=290991 including backing up my system state and deleting regisitry keys. I went as far as I could removing all known instances and using full text removal. When I try to reinstall, my old del
eted instance name is the only one that appears in Enterprise Manager and of course I cannot see the instance I tried to install.
Deinstalling the instance I just triesd to install, I went back to look at the registry again. I noticed a registry folder under LOCAL_MACHINE>SOFTWARE>MICROSOFT that was named SQL_REDIST containing a folder named 1.00.000 and one named Setup.
Should these also be deleted?
Thanks!
I seem to have reinstalled successfully.
I went back through the new install procedure and made sure to name a new instance instead of taking the default instance in the wizard. I named the new instance the exact same name as I had on the Evaluation Edition instance and everything now seems to b
e working.