Amazon sells the adaptors. Check out my build thread as i recently installed my stereo. The colors are industry standard.
White- front left. Gray- front right. Green- rear left. Purple- rear right. Red- power. Black- ground. You probably have two factory wire harnesses. The smaller one is for the dash speakers.
Do not forget to unhook amps in back for subwoofer and front kick panel. I blew the fuse before I looked it up on here.
Now it works great.
Pioneer speaker replacement is very cheap and they sound 10X better then stock. One of my best upgrades