I've got a pair of jl components in mine, fitting tweeters is dead easy. Pop the factory ones out and use hot glue to fix the new ones up against the back of the hole. That way you can remove them easily and the hot glue will just peel off. (also it doesn't matter how big the tweeters are)
To get the best out of them remove the black foam cloth from behind the tweeter grill as this really takes the edge off the treble. Good Luck!