How do you replace the tail light circuit board on a 1989 Volvo 740 GL sedan?

To replace the tail light circuit board on a 1989 Volvo 740 GL sedan, start by removing the tail light assembly by unscrewing the bolts securing it to the body. Once removed, disconnect the electrical connector and carefully take out the old circuit board. Install the new circuit board by aligning it with the assembly, reconnecting the electrical connector, and then reattach the tail light assembly to the vehicle. Finally, test the lights to ensure proper functionality before securing everything back in place.