A rear-view mirror is a functional type of mirror found in motor vehicles, designed to allow the driver to see the area behind the vehicle through the back window. Here's a photo.
"to stuff oneself with something" has two meanings. (1) to eat until you are more than full of food. (2) to place a foreign object under your clothing; e.g., a Santa Claus costume, a pillow gives the appearance of a large belly.