You want to change the gray to black. Scuff sand the area and use paint meant for auto bodys. That small of an area a can of duplicolor spray should do just fine.

man that would be pretty tight with the white and blue, i want black bcuz im thinking about getting that front air dam off of pfyc and painting it black, kinda like a splitter type thing

seems like an awful lot of work to repaint the bottom section. I also just put the inserts in.