How to eliminate the Found New Hardware Wizard?

Synopsis:

I have XP Professional installed on 8000 machines and I'm
using Software Distribution systems to deploy the
operating system and additional software to all of these
machines.

When we created the XP image, we forgot to include drivers
for 1 piece of hardware. It's a USB Point-Of-Sale printer
and comes with 'Unsigned' Drivers.

I've delivered the drivers with the Software Distribution
system and even modified the Group Policy so Unsigned
Drivers will 'Silently Succeed', but the 'Add New Hardware
Wizard' still appears (even after a reboot).

If a user clicks 'Next', then 'Finish', the drivers are
successfully located and installed... but we don't want
the user to have to do this. We want the drivers
installed automatically without any user intervention.

Is there anything we can do to accomplish this? (I
realize that the Wizard is there for our own protection,
but would like to - at least temporarily - turn off that
protection)

Thanks in advance,
Jim