Merziac am I tracking right from your pictures:

Use the Sugino to hook into the locking ring notch.
Then use the adjustable clamp to clamp the Sugino tool tight into the against the bottom bracket.
So that when you have to apply torque through the Sugino hook tool if you wobble while doing so it doesn't allow the hook to escape from the locking ring notch rounding or chipping a corner off?
Not clear on the square board (?) is that to expand the grip of the adjustable clamp?

Did it get it right, as that would really help to keep the hook in the notch no matter how the handle wobbles so they are engaged fully rather than slipping loose and rounding or chipping off a corner of the locking ring.