The First Thing To Purchase...

what should i order first my deck my subs n wiring kit my amp or my box?

head unit doesn't matter when you order, but your not gunna be workin w/o it. Get your subs then an enclosure for them. Then get an amp to match them. Then get an install kit w/ the right guage wire.

Wow... I really disagree. The one thing you will always regret not having is a good headunit, I would get the headunit first, then you can run RCAs instead of whatever is used on stock. Also I would see if you can make an enclosure based to sub specs

that is some DAM GOOD advice haibane, i wish someone told me before i bought an amp.. i got subs from my aunt for free, so i got an amp, that matched the rms (also a mistake) at first i had to buy the amp, then the LOC or line output converter, it sounded so crappy, til i bought my head unit, then everything became clear, this was how i got my system started

if you KNOW you don't want the OEM (factory) headunit, it might be easier or cheaper since you won't need a LOC. It's always cheaper to buy what you want the first time.