Hey. I'm relatively new around here. I just picked up a 2004 ES330. OK, I got a few questions. What are my realistic options for upgrading the sound system? I know I can change out the speakers. How hard is it to change the tweeters in particular? How powerful is the stock amp? How hard is it to bypass the stock amp? Has anybody installed a full system? If so, where have you guys installed the crossovers? I've got questions. You've guys have got answers. :D Thanks.