I've annotated the circlip photos to show what I mean. The bevels on the inner and outer radiuses are on opposite sides. I have installed mine following the outer radius beveled edge as the one indicated in the manual. So the outer bevel faces the item pushing on it, which does mean that the inner bevel is towards the side of the groove that has been cut in the shaft that would have the force on it. That follows what wikipedia (that couldn't be wrong surely) information on external circlip orientation. This shows that the radiused arc should be away from the force on the inside radius, so it sits nicely in the groove.