Running new wiring is a fun job, what do you mean Jay? I rewired my entire car, with my Amp in the boot on my sub box. you just have to pull the kick guards off from the floor and run the wires along there.
When you get 6" speakers, make sure they have the mounts that stick out slightly from the main holes. most pioneers have this and i think clarion and kenwood. i've hooked up all pioneer speakers in my car. i had to cut the back of the speaker mounts off as the new speakers were much deeper. when/if you do this, be very careful, as i found out mine was shorting on the car which was causing the whole system to crap out.
Another thing i found, don't worry about how loud it is for the cops sake, the stagea has some pretty good sound deadening in it, and i can hardly hear mine even whenit's cranked up to full (2 x 10" subs)