Hi all,
I've found a way to tackle this problem. First ItemRenderers are completely separate entities, they know nothing of each other so I can't get the widest item in the way I tried. I've now set the width of the whole component in the main mxml to 650. In the itemRenderer I just put subtract 650 if I want the icons to go to the left and add if I want to go to the right. HTH someone.