Yes, you can replace a tail light assembly yourself! Depending on the make and model of your car, the process may vary but for most vehicles it is relatively straightforward. To start, you'll want to gather up some tools such as a screwdriver or nut driver if necessary. You'll also need replacement bulbs and an original equipment manufacturer (OEM) tail light assembly specific to your vehicle's year, make and model. Once you have all of these items in hand, turn off the engine and open up the trunk or back hatch of your car. From there remove any screws or bolts that are holding the current tail light assembly in place before disconnecting any electrical connections between it and other wiring harnesses. After this step is complete carefully take out the old unit and install its replacement by reversing each step taken while removing it earlier. Make sure to securely attach all mounting hardware with screws or bolts when finished reconnecting all wires properly to ensure proper operation when turning on lights later on down the road!