wiring kit

I have an amp wiring kit, but im not sure if i have all the wires. I have the two red wires and they both have fuses. One of them is an 8 gauge wire and the other wire is a 5+ gauge with a 100A fuse. the twisted audio cables. I have the remote turn on wire too. I dont know if i need anything...

I have a pioneer gm-d8400m amp and a 12" sub. What type of wiring kit do i need? 4 guage? I also plan on buying 6x9's and 6.5's. Do i have to power those through the headunit? Is it better to upgrade to an aftermarket one? Sorry im a newbie to car audio.

WTB: 2 or 4 Gauge AMP / Wiring Kit. Anyone here have wire for sale? Or know where the deals are online?