Don't forget to do last bit of sanding of the front opened grills and bumper before you paint. Always stick with a white primer on lighter colors including red,white,yellow,and light greens and blues. Good luck.
BTW I don't know if you airbrush or not, but what i have been doing lately is : if the paint color is going to be lets say orange, i add a few drops of orange paint to white primer. And what you get is a light orange primed body, i use this method on Tamiya TS paints decant.