steering stem ring nut socket

[blade625]

has anyone come up with an alternative to the "ducati" tool for tightening the ring nut on the steering stem? I'd like to torque it to spec [12 nm] but it is another one of those nuts with the four "castle" cuts in it similar to the cam sprocket nuts [which I made my own tool for...but this is much larger dia...like 45mm]

I know that lots of 4x4 hub nuts are like that also, has anyone found an alternate socket at an auto parts joint?