I've seen topics on here about people installing HUD in 2003 and older Prixs, but I can't seem to get a definitive answer on what it's like trying to put an HUD unit in a 2004+, mine in a 2007. I don't have HUD now but I see people getting them from junkyards and there is even one on ebay right now. How big of a feat is this? If i get the wiring harnesses out of a model with HUD does it all sort of plug and play, or is there wire splicing etc. involved?