The OBM is not removed ...
... when trailering. Per the factory, a 50 hp OBM is the standard with select dealers authorized to install 70 hp motors. It is implied that the factory will not honor the warranty is there is a transom/hull issue and the owner has too large an OBM hanging on the stern. To answer your questions, a 50 HP unit is the standard with quite a few people reporting that they have installed 60, 75 & 90 hp units. I have a 50hp Suzuki on my 26M and no, you do not remove the OBM when you haul the boat around the country.