Disabling the Navigation Pane through Group Policy?

Hello,
I'm on a mission to disable and hide Vista's Windows Explorer
Navigation Pane from the end user. I'm aware, that it can be hidden
through Organize->Layouts, but it can be toggled back on with the same
option.
There are explicit Group Policy objects to hide the Details and
Preview panes, but I have not found a suitable option that applies to
the Navigation Pane.

According to the Vista User Experience guide (http://
download.microsoft.com/download/b/0/4/b04f83c7-ef12-4d16-9df7-
cd5ce0d068de/Windows_Vista_UX_Walkthrough.doc) I should be able to
disable the Nav Pane using the GPO: User Configuration >
Administrative Templates > Windows Components > Windows Explorer >
Turn on Classic Shell = Enabled. I was unable to successfully do so.
Any suggestions would be greatly appreciated. If you have a non-GPO
way of permanently disabling it, that would work for me also.
Thanks,

Jamie