Been overheating the last couple days in my 87 w/4.0. Flushed the system, new thermostat, new pressure bottle and cap. Also installed a mech temp gauge. The electric gauge reads almost 260 and the mech reads about 200. Also I put a oil catch for blowby and instead of it catching oil it catches water and there is a thick foam inside the bottle. Do you guys think this could be the head gasket?