remove the flywheel and stator plate. then remove the seal. you will want to have a replaacement handy. you will probably distroy the seal getting it out. drill a small hole in the seal and screw in a screw that does not have a pointed tip. then pull the screw to extract the seal. this may take a few trys to get it right. be carefull not to damage the bearing or the seal housing durring this process. check the seal housing for scratches or burrs. if it is clean, install the new seal using a large socket or pipe to force the seal in all at once. make sure you fill the groves with the springs in them with grease before installing.