okay, so I took everyone's advice into consideration and ordered all of this last night, did i miss anything or order any wrong items? thanks again:
PIONEER AVH-X4800BS 7"
Polk Audio DB651s Slim-Mount 6.5-Inch Coaxial Speakers (Pair)
Rerii 2 Meters Length USB & 3.5mm AUX Extension Flush Mount 6.5 Feet Audio Cable
Metra 99-7607B Dash Kit for 2009 Nissan 370Z (Matte Black)
Scosche Radio Wiring Harness for 2007-Up Nissan Car Stereo Connector
Stereo Antenna Harness Adapter for Installing a New Radio Into a NISSAN, 370Z,
2009, 2010, 2011, 2012, 2013, 2014, 2015
Steering-Wheel-Control-for-PIONEER-Headunit-Retains-OEM-Radio-Functions-SWC-MN
Steering Wheel Control for Pioneer Headunit Retains Radio Functions SWC MN | eBay