Take a look at
this photo. You can just see the front casting hole (freeze) plug located between the water pump and timing gear cover. So, you don't have to remove the water pump to replace the plug. Ensure you get the correct plug from one of the many vendors. It is basically a concave/convex steel disk without a perimeter lip/flange. Remove the old plug by drilling a hole in the center, threading in a screw and pry it out. Clean up the hole and apply a suitable sealant around the perimeter "ridge/step" in the hole. Insert the plug convex out/concave in. Finally, using a ball peen hammer and a regular hammer: place the ball of the hammer on the center of the plug. Hit the ball peen hammer with the regular hammer to indent the center of the plug. This locks it into place.
