Welcome to another Impreza owner installing a CarPc.
If its any use to you, i am also installing a CarPc in my Impreza and have done a few graphical customisations to different skins etc.
My WEB site is at www.wrx-carpc.co.uk
Best of luck and its looking good so far !!
PS. Out of interest, what software have you used to do your wiring diagram ? I'd like to do something similar if you could send me the source file it would be appriciated. Email link is on my site.