You have freeze plugs down either side of the block and in the front and rear of the block as well. here is an image of the locations and how to change them out as well. Check out the tool they use to do the job. Check out the images (below). Please let us know if you need anything else to get the problem fixed.
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.