Blindly installing bootcamp

Hi

My 2012 Macbook Pro has broken LCD. I use an external HDMI monitor but the display signal only becomes available at OSX/Win7's log-on screen.

This means when I reinstall Win7 via Bootcamp as soon as the Mac restarts I become blind. I do not know if Bootcamp is automatically installing, or are there buttons I need to press.

So is it possible to install Win7 like this?

My thread about the broken HDMI monitor not getting signal is:

https://discussions.apple.com/thread/5592539

Thanks