Its normal to use a bushing in the spinner backplate to reduce the hole diameter. Smaller spinners often have 1/4” holes and larger spinners have 3/8” or 10mm holes. Many times these bushings are provided with the spinner but if not they are usually sold as an accessory. If you can’t find one, many of us have spares and would probably just send you one in the mail if you make a request with size needed.