An apparatus and associated surgical method for repairing abdominal aortic aneurysms is disclosed. The apparatus includes first and second stent grafts made from a metal form structure in combination with a flexible fabric, and a flexible guidewire detachably attached to the first stent graft. The first stent graft has an upper tubular body which defines an inlet, and a lower bifurcation which includes a first tubular leg defining a first outlet, and a second tubular leg defining a second outlet. The method includes advancing the first stent graft through one iliac artery and deploying it in the aorta, advancing a guidewire engagement device distally through the other iliac artery and pulling the flexible guidewire into the other iliac artery, advancing a guide catheter over the flexible guidewire into the second tubular leg of the first stent graft, replacing the flexible guide wire with a stiffer guide wire through the guide catheter, and advancing a catheter delivery system provided with a second stent graft over the stiffer guide wire into the second tubular leg of the first stent graft.