I'd say take a look at Infinity Kappa Perfects (While I'm a huge fan of Alpine, the Kappa Perfects are so crisp at high volumes).
For headunit take a look here:
Kenwood DNX6140 install
A Kenwood unit seems to be the best overall choice to go with, from my research the DNX6140 being the better unit even of newer ones to go with as the newer models seem to be prone to crashes and random restarts(what I've gathered from my reading around).