New door speakers in MY04
 

Right, I'm about to upgrade the door speakers in my MY04. I'm currently thinking Boston Acoustics (bit expensive!), Infinity (I listened to some Inf 6522SI which were nice) or Pioneer (were good in my old car), but that doesn't really matter. The thing is, with the MY04, there are main speakers and tweeters. So do I:

Swap both, plus the crossover (if there is one)?
Swap the main speakers with new full range and ditch the tweeters?
Swap the main speakers with new full range and keep the tweeters?
Swap the main speakers with component mid range and keep the tweeters?

Bear in mind I have the headrest speakers too (the two mid/tweeters in each headrest) and I'd like drop-in speakers if at all possible. I'm reasonbly happy (ish) with the sound quality of hte stock speakers, but would like added clarity and volume for those high speed roof down moments.

Suggestions appreciated! It'd be a lot simpler with no tweeters, damn these newer MYs!

Chris