also
http://www.sonicelectronix.com/item_3689_Metra-82-6901.html 2 sets of these
http://www.sonicelectronix.com/item_22347_The-Install-Bay-VXT65.html for some added water protection if you want. it's best to cut the bottom side out if you purchase these because the speaker is designed to work free air and these cut the air off.
http://www.knukonceptz.com/ this is where i'd suggest getting all the wiring from.
if you want to avoid ordering it all to specifically fit your needs just order a 0 gauge an 4 gauge amp kit. KCA kits are copper clad aluminum which is cheaper but still fine for what you're doing.
big 3 wire will be 1/0 gauge power wire. you will actually only need to replace 2 of these 3 wires since the battery is in the trunk.
talk to the audio shop about this and they should be able to do it for you there. order some
http://www.knukonceptz.com/mobile-audio/power-wire/kandy-kable/ 6 feet would be plenty to be safe and pick a bright color so you can be damn certain they actually do it because some shops are shady as hell.
the engine block to body ground is the only problematic wire to replace yourself while the others are easy to get at and do it's somewhere down on the side of the car engine lol.
when doing the ground MAKE SURE the paint is removed from the ground spot and its a tight connection. don't let the shop cut corners on grounds and check them before you take the car.
now onto the box lol
you'll need to figure out what kind of tuning you want to go with. you can go recommended specs
http://sundownaudio.com/index.php/products/subwoofers/item/sa-series.html or tune the port a bit higher or lower depending on what you want.