danzcool

Wrong!
The cluster itself needs to be reprogrammed, you can send your cluster and overlay to Saleen and for a fee they will reprogram it so that it is accurate, I did it. It's not cheap, in the end it cost me about $300, but that included the overlay from ebay, the shipping to and from Saleen, the programming and new needles. Maybe they stopped doing it, but I doubt it, it's easy money and pure profit for them.

Otherwise you can probably fudge the rear end ratio and tire revs per mile with a tuner so that the MPH appears to be accurate to the observer, but this will cause the odometer to be inaccurate and the RPMs will still be wrong. Unfortunately you should have just bought a new GT cluster from the dealer instead of having the stepper motors replaced, shouldn't have been much more, I thought I was hearing $350 for the cluster.