Glad to hear you're gonna take the plunge.
Not sure how the '03 speaker set-up is, but if you want 6x9's, within the $120 range, i hear good things about
these. I have
these and I think they're fantastic! But be sure and go out and listen to stuff that suits your tastes.
They only tough part about my install was probably running the wire from the door to the interior, guiding it through the grommet thing, frustrated me to no end. Other than that, I just dropped mine in and hooked 'em up. Work like a charm too. Maybe a baffle or something depending on fitment issues. And if you plan on adding onto your system, I'd look into sound deadening. Hell, even if you're not adding more to your system, sound deadening is still great, and it makes for a smoother, quieter ride. Just a thought though.