The other think is that I could not find M10 pin. And I would like to have M10 because this is the correct size. Alas, the bolt and most pins are not tapered enough to make it easy to plug the pin. You need to fish around the get all the holes lined up with in the connected mode. And I want that to be easy.
What about using a smaller pin, and a sleeve to adapt the smaller pin to the M10 size?