I have a 1993 Pontiac Firebird Formula that originally came with a 115mph speedometer instrument cluster and I just recently picked up a cluster from a 1995 Trans Am that has a 155mph speedometer. I have just over 100,000 miles on my cluster and the 155mph cluster has 98,000 miles. My question is, does anybody know how I can chage the new cluster's millage to read the same as my original one when I swap them out?