I have an old snapper, so old in fact a snapper rep couldn't tell me what year it was by the model and serial number. i need to replace the drive disc/friction disc, it has a lining on the inside and a thick rubber lining on the outside that determines what gear you are in as it moves on the wheel that advances the speed of the mower. My question is , has this part changed any in size or bolt holes or anything over the years, i need to know in order to get a new one..

Tks

rick