I bought a McKee 720 and have fixed it all up. Now I am confused how to hook the PTO shaft to the implement. It is my first implement. The PTO shaft at the implement end has a key way and the connection on the blower has a key way and what looks like a shear bolt that has sheared and stuck in the hole. The two key ways seem to be different sizes. There is also a small bolt on PTO knuckle. I have included pictures. Any help appreciated. THX.