buy the hch and talk to tbaleno about installing sub decks in your trunk. he's currently working on that in his hch

you are correct that replacing the prius' head unit is more difficult than the hch, and i believe you must take out one of the screen console components - can a prius II driver affirm or deny?

with the hch you can just slide out the head unit, detach audio/power/ant and reattach to new unit, just like any other civic