I am wanting to reseal the lower unit and the seal kits I am seeing one is from 1960 to 1973 part # 18-2686 the other seal kit is from 1976 to 1988 part # 18-2659 where is 1974 and 1975. is seal kit 18-2686 the one that I need it looks like the one I need cause it has the spaghetti seal in it...