1985 Mercury Lynx How to replace a timing belt in 1985 Merc

Engine Mechanical problem
1985 Mercury Lynx Manual

My son is without transportation to and from work and someone is offering to give him a 1985 Mercury Lynx. The catch is that it has a broken timing belt. They have the belt to give us and my son has a great deal of mechanical ability but has never replaced a timing belt. Also, I have read that there is a possibility of engine damage in this car if the belt breaks, which is why they recommend that it be replaced at 60,000 miles. Is there any way of telling if the engine has been damaged before changing the belt? Can you give us some direction or instructions on changing it? Can you provide diagrams that will help? We don't have much but do have a desire to succeed and any help would be greatly appreciated. Thank you!