The gear case lube should have been changed at the end of the season it was last ran. You should check to see if that is the case. That is a good indication if it has, and may indicate its ready to go. If it hasn’t, and there is any indication of water, I would be apply your same method for the carb and gas tank, while inspecting its condition before using it. It would be a good idea to clean and check the gap on both sets of points. No matter what ignition you have, replacement coils are not available for the Phelon or the Bendix. There are substitutes coils that require some modification.
A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.