i have an 88 gt that has the stupid 85 mph speedo. i bought and installed the white face gauge kit that has a 140 mph gauge face and of course the speedo isnt correct now. Does anyone know how to fix this? Do i need a whole new speedo or is there a new gear i can put in to recalibrate it? What year did they change to the 140 speedo in case i need to buy one of those? Sorry for all the questions but thanks in advance for any help. Also my car is automatic if it matters. Thanks again.