Activate 8.1 Pro with 8.0 Pro upgrade key

[Blackcom]

I know there is a registry trick that will let you activate a fresh 8.0 install with an 8.0 upgrade key.
But does anyone know if I can activate a fresh 8.1 install with a 8.0 upgrade key using the same registry trick?

These are the tricks i've read about:

Activate fresh install with upgrade key
Press the Windows key and type regedit. Press enter to open the Registry Editor.
Navigate to HKEY_LOCAL_MACHINE/Software/Microsoft/Windows/CurrentVersion/Setup/OOBE/ and double-click on the MediabootInstall key in the right pane.
Change the key's value from 1 to 0.
Exit the Registry Editor, press the Windows key again, and type cmd. Right-click on the Command Prompt icon and run it as an administrator.
Type slmgr /rearm and press Enter.
Reboot Windows.

When you use the Windows 8.1 ISO created by the Setup process above, you will need to enter a generic placeholder Windows 8.1 product key to get it to install (as explained in a superuser.com thread). Use 334NH-RXG76-64THK-C7CKG-D3VPT for normal, or XHQ8N-C3MCJ-RQXB6-WCHYG-C9WKB for Professional (these keys only work to install and cannot be activated). Once Windows is installed, you will need to change the key to your key. To do that, Right-Click the Start button and start the Command Prompt (Admin).
Type the following commands:
slmgr /ipk YOUR-KEY-WITH-DASHES-HERE
slmgr /rearm
reboot you computer and it should be activated.

First installing Windows 7, THEN installing Windows 8 and THEN installing Windows 8.1 sounds so dreadfull i'd rather avoid this method.

Any help would be welcomed.

 

[theog]

http://www.eightforums.com/installa...retail-windows-8-1-windows-8-product-key.html