A.
anwered by: canteau
The CenterLock lockring uses an outboard bearing bottom bracket tool for installation and removal.
The socket type tool can be found here :
http://www.treefortbikes.com/product/333222345088/283/Park-Tool-BBT-192-Bottom.html
The wrench type tool can be found here:
http://www.treefortbikes.com/product/333222335894/283/Park-Tool-BBT-9-Fits-Shimano.html