Nearing end of mini project and am wanting some noise in my car

I have some infinity 6x9 in my peugeot daily road car, which i will be selling, so will proberly take the speakers out.
I also have some Jbl Gto626e grand touring series 6.5" 180watt 60rms speakers that are boxed and have not been used yet!
i was planning on putting the jbl speakers inthe dash vents, but there 5 cms too big!
SO i dunno what to do ?
Put the infinity 6.x9s in the parcel shelf and buy some tweeters ? to go in the air vents in the dash ? ( can someone explaine a abit about tweeters please! ) the 6x9 s are aparently 300watt peak , and 100 rms ? over kill ? not good in the back ? would the jbls be better?
or put the jbls in the back and tweeters in the front, or put either speaker in the back, and buy some 10cm speakers to go in the vents ??
basicaly what would be beter, 10cm speakers in the dash vents, or tweeters ????
I do have a amp, but id rarther run all these off the headunit please!!
by the way id much rarther have sound quality over loudness!!!! however i do need to be able to hear it over my engine....
Thanks

Dave

Edited by Mini-Dave, 03 February 2007 - 11:13 PM.