I will soon be acquiring a spare digital dash for a 1987-1988 Trans Am GTA and need to know how will I be able to retain the low mileage of my original car when the time comes to use the replacement dash odometer electronic module. Hope that it is as easy as swapping a removable part on the odometer integrated circuit board. The Pontiac Service Manual is worthless for finding this answer. I would appreciate responses from those who have had to perform this function....