The GM Goodwrench site has finally updated with some new vehicle body structure information. Take a look at the image of the picture below to find where UHSS is used on this vehicle platform.
No surprise that the body side is reinforced with Ultra High Strength and Dual Phase Steel. The Front Floor Panel Reinforcement (10) and Body Side Inner Rocker Panel (11) are made from UHSS. The Body Side Inner Reinforcement (8) and Front Lower Rail (12) are made from Dual Phase steel.