Do the lunge as you did on page 1. Once you get your hip stretch happening, increase the dynamic of the whole stretch by letting your shoulder blades slide down your back as you reach your arms overhead. You might shift back a little more, but don't let your ribs pop forward. The focus of the stretch is still through center, and the front of the hip.
Be sure to keep your legs in parallel, and your hips and shoulders even. Enjoy!This stretch is similar to Yoga Warrior 1 pose except the legs stay in parallel, whereas in Warrior 1 the back leg turns out and the heel goes down. As usual, I suggest you try both!