Travis,
I don't recall seeing that color you're suggesting on a mustang before so it sounds pretty unique. Though, the King Ranch cinnamon color I think you're talking about may be a little too rustic (trucky) looking for a car.
Link here:
http://www.autorevue.cz/Obrazky/2006...rbes/F1502.JPG
One other thing to consider with that color is it only looks good with tan interiors, black or charcoal would look bad. I just wouldn't want you to be limited on what you can do with interior.
If you're leaning towards copper/cinnamon colors check out 05 Infiniti G35 Garnet Fire...it's in the same color family but looks a lot sportier. Just a thought. (couldn't find a photo that does the color justice online)
If you are still having a difficult time after getting the feedback you are looking for, you could contact one of the artists/designers on the artwork page. I'm sure one of us can help you visualize what it will look like so you don't get paint choice regret after the project is over. That's never fun.
Good luck!