set primary monitor during install

[Andras Simon]

I'm trying to install F18 on a netbook with a small screen where
most of the installer's screens don't fit. To get around this
problem, I attached an external monitor - but now the installer
thinks that's a second monitor, so I still can't access critical
parts of some of the installation screens. Is there a way to
specify the external monitor as the primary one? Or to just use
the external one?

Andras