I am changing out my mercruiser engine(which has been blown)off my 1975 wellcraft to a 165 GM inline 6 automobile engine. I know I need to change the plugs to brass, the head gasket to stainless steel and a new camshaft. My question is what else needs to be done to the engine since everything else internal is the exact same as a marine engine. I know I will get a lot of flak from the more experienced guys about the differences but this boat was given to me so I am not out anything yet, also this boat will be run in saltwater. Everything else works excellent.