Welcome to MP3car.com fellow Suby owner.
I have a STi and plan on using the in-dash VGA.
What model Impreza do you have? I'm assuming the console is the same as mine, or similiar. On www.imprezawrxsti.com this guy put a screen in. http://www.imprezawrxsti.com/postnuk...ewtopic&t=4899
Take a look, I measured and the liliput doesn't clear it. You need to hack the plastic.