In my F-Car (sorry if this annoys people when i mention ferrari i dont wish to rub anyones nose in it,beleive me you wouldnt want an older one )

...ok got that over with,i want to upgrade the shitty sound system although it has a hi end alpine radio cassette it sounds pony ..i have got a wicked alpine head unit which has a 4 x 60watt max power output.....now i cant go subwoofer or amps..all i have got is 2 x door speakers i beleive around 6 inch round with 2 x tweaters on the dash (ferrari install)...now i want alpine speakers in there what is the best to go for to get the best sound and do i need seperate tweeters?...I could put a pair of 6 x 9's on the rear shelf although i could only mount them in the pods and put them so the headrests block there view..although i am thinking it might look shite...any ideas guys,i know the engine noise is the ICE but i want some ICE T playing