ok, i have a 92 t bird lx, it had the digital dash, i converted to the 6 gauge anolog of a 94 bird, everything works but it has to 120 speedo and its 10 mph off, IE when it says im doing 35 im doing 45 if it says 55 im doing 65, i have a brand new speed sensor in the car i dont know what is going on, any suggestions?