A bus has three examples of a vehicle signal light assembly. Each assembly includes a housing base with a perimeter wall defining a cavity. The cavity includes an end portion set off by a partition in the cavity. Separate circuit boards are disposed in the end portion and the remaining portion of the cavity. Each circuit board has an array of LEDs that convey a message. One circuit board can be positioned in the end cavity portion in at least two different orientations. The end portion of the cavity and the one circuit board are preferably octagonal in shape to accommodate several orientations of a circuit board having arrays of LEDs arranged in symbols such as an arrow or a stop sign.