16. Our old gauge cluster housed a mechanical speedometer, which used a cable to manipulate the needle in the gauge. Our 3650 uses an electronic sensor. Auto Meter sent us a Pro-Comp Ultra Lite speedometer to match the rest of the gauges in our cluster. The Ford Racing Control Pack has a lead for an electronic speedo, so hooking up the gauge was as simple as finding the lead under the steering column, and plugging the harness into the new trans.