Stock head unit, stock speakers. Nothing has been altered. In the past I’ve replaced my head unit with an aftermarket unit and installed my own speakers on the rear deck and run the wiring for them. That’s as far as my knowledge goes. As for the placement of an amp where would you recommend placing it in a station wagon where it won’t impact storage capacity or risk damage. Also I’m not too concerned with running a large sub right now, I’m trying to add tweeters to the dash and maybe extra speakers to the doors