Marine carburetors will have very specific float settings per application. Some will be listed quite low due to the mounting angle, etc.
Most carb numbers show up in the instructions, I would set the floats at the factory recommended setting. If no listing is found, I most often set them at 1/4". Marine applications are sensitive to high fuel levels, and fuel slosh, etc, and running a 1/8" setting may produce running rich and even stalling issues in actual use......Cliff