youll have two 1/4 pipe plugs on the sides of the block,one on each side ,mid blockish down by the oil pan rail,remove those use a nail or small srewdrive to clean out debri and get the water flowing out ,also pull off the hoses to your exh manifold-logs ,and drain those
next pull off one of the hoses at the thermostat houseing and start pouring in rv antifreeze,did you put the side plugs back in and reconnect the hoses sorry,fire the motor up and fog it ,your done
in your climate drianing will be enough