That was the original paint job for Optimus Prime actually, but every time he transformed the image of Chuck Norris was so resistant to any warping or bending that the section of truck where his image was would peel away, taking steel and other cybertronian doo-dads with it. It was tragic, but they had to do a complete redesign in the middle and settle with an Optimus that was just that much less cool and tough. More an emotional hero for the masses.