** Speed Calibrator: pt# LRS6519 - Allows owners of 99 & new mustangs to change the rear gear ratio or wheel and tire size. Includes: male and female connectors and instructions. Requires cutting and splicing in order to install. 99-04 $99.95 each.
** Electronic Speedometer Ratio Adapter: pt# ERA100 - Allows owners of 99 & newer mustangs to reprogram their electronic speedometers. 99-04 $129.95
Any question about these items directly should contact Mustangs Unlimited -
Georgia: 888-229-2929
Connecticut: 888-398-9898
98 and older mustang owners are stuck changing the Transmission and cable gears.