I haven't installed it myself but, the only thing I can think of that will show your speed would be "VEHICLE ROAD SPEED SENSOR". If someone can confirm?
If that's right locate your ecu under the passenger side kick pannel tap into the the YELLOW-WHITE (VEHICLE ROAD SPEED SENSOR / VSS SIGNAL) wire and connect the 'purple' from your turbo timer. Tape it up and your good to go.