Here is the whole deal (if your door handle is in the middle of the door).
1. remove the door handle an manipulate the handle gizmo so that you can un-hook the rod that goes to the broken latch. **advise you tie a string to the rod end so, if it falls down into the door, you can retrieve it.
2. drill out the rivets and remove the latch mechanism. Un-hook it from the rod end.
3. hook rod to new latch mechanism and rivet that into the door end.
4. retrieve the handle end of the rod, re-attach to handle mechanism and re-install handle in the door.
5. pop the cap on the cool beverage of your choice

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The best way to preserve these latches is to never slam the door but close it gently and press on it with your knee/lower leg to latch it. This is especially true when it is cold.