CJ hardly ever does codes anymore unless its some holiday special. American Muscle ditched most of their discounts unless its some random catalog code. I know if you know someone in the military they can call an order in and get a discount.
One of the guys from CJ Pony Parts (I think it's Bill) is on the forums, and if you find and PM him, he might give you a code to use. One time I got an 8% off code from him several years ago, so might be worth a shot