The following oil seals can be replaced without removing the transmission from the car, namely the speedometer gear seal and the extension oil seal. To access closer to the vehicle, lift it and place it securely on jack stands. Remove the speedometer cable, unscrew the lock washer and the extension bolt and take off the lock plate. Using a screw driver, the fitting gear and shaft needs to be removed from the extension and the O-ring at the same place. As for the installation, reverse the removal procedure and do not forget to cover the new seal with the transmission lubricants, also, the positioning of the assembly should be so executed that the key-slot in the fitting should be placed opposite the lockplate boss on the extension. If required, extension oil seal remove the drive shaft and other related accessories for more clearances for easy fixing of the extension oil seal. From the carburetor carefully pull out the old seal, and scrape the counterbore area to ensure it is free from any damage. Before assembling the new seal put some transmission lubricant between the lips of the new seal as well as applying an appropriate sealant on the outer diameter of the seal. Fit it with lips turned inwards and should only be adjusted once the flange comes in contact with the seats, preferably a tubular spacer should be used at this stage. Last of all, replace any other components you might have un-mounted such as the drive shaft.