forcing windows to install on mbp external screen

So here's the issue. My macbook pro works totally fine except for the screen...which is busted. This is totally fine since i use it with an external monitor. The problem comes when I try to install windows on a boot camp partition.... the windows installer will only use the internal screen and i can't install since i can't see the screen to answer questions... I tried using an unattended install but even those require minimal input and don't work. So... is there any way I can force it to use the external screen for the install? (or any other solution i haven't thought of yet)