Figure 4: " Because the old and new transmissions are mounted in identical positions, the next step was to determine the length of the transmission shaft housing between the inner mounting surface of the windshield frame and the bottom of the knurled pivot.  We found this to be two inches -- measured from the top of the mounting surface to the end of the transmission shaft housing.  The measurement was transferred from the original to the new unit.  We measured from the top of the 5/8-inch spacer washer toward the end of the shaft housing."