Method for modifying an existing vehicle on a retrofit basis to integrate the vehicle into an information exchange system in which the vehicle includes a processor arranged to receive information and use the information in the operation of the vehicle. A communications device is coupled to the processor and can be used to establish communications with other vehicles or infrastructure to receive information from the other vehicles and infrastructure and/or provide information generated by the vehicle to the other vehicles or infrastructure. The received information may be displayed to an occupant of the vehicle on an existing display.