We have an Ambassador cutter on the Saildrive/Two-Blade Folding Prop of our 365GL.
I had to replace the prop hub a few years ago and in order to fit the cutter, the Volvo hub had to drilled with two small holes either side of the splined-core. A marine engineering firm did mine. They were used to doing them and had the exact setting-out and hole dimensions required.
I still have the old hub and attach a couple of photos.