Push button interface Module (Signal Convert to 8,000 or 16,000 rpm)
Dip switches on the speedometer are difficult to reach once the gauges are installed so the purchase of a SN74 (signal interface) is recommended to make the speedometer calibration easier. The senders are standard as SNGMNF (Sender GM, no Fuel). Fuel gauge is calibrated to match the factory sender (0-90ohm).
Also see the GPS Sky Drive Antenna for speedometer calibration.