Is it possible to add a factory power tilt unit to a 1971 125 HP Johnson(125ESL71C)? Does not have one now. Would I have to change mounting bracket? Would rather use a factory unit and control box then an aftermarket one. Any suggestions would be great. Boat is a 1971 Glastron tri-hull. Replacing rotting floor and rebuilding the transom, so motor will be off boat.