My new Mercruiser 350 Mag MPI raw water cooled engine has 5 blue drain plugs. Is is really as simple as unscrewing all five plugs, waiting until all the water has drained, and then putting the plugs back in?
Be sure to poke the holes with a nail or screw to make sure no blockage has taken place and some will also remove the bottom hose of the water circulation pump on the front of the engine.
Bravo drive on a trailer? Might also want to make sure the raw water pump has no water in it.
