hi william. I whipped up a quick sketch of a camaro. The proportions aren't great, neither is the entire drawing, but I hope it's good enough.
About the curvy stripe thing across the side, that could be used to divide the car into 2 different colors if you want 2 tone. you could make the thin strip a different color as well.
Alex
*Edit: i just noticed the pic quality is bad, if you would like a re-scan in better quality for a photoshop rendering, feel free to tell me