I must disclose that I represent an electric propulsion company for sailboats. That being said, we have been removing engines and replacing them with electric systems. The real trick is to remove them without hurting or sinking the boat, both things can happen. We have not had to cut fiberglass but I am sure that one day we will need to do so. We would recommend the removing of all parts of the engine to reduce its footprint. You might need to build a jig to attach the motor to a hoist. Additionally you may need to rotate to move up or forward. You might have the misfortune of owning a boat that the engine was installed during the build/layup construction phase, but that is not so common. Think outside the box and be patient.