I have a 1948 Plymouth special deluxe convertible I am trying to repair gasket from transmission to bellhousing and noticed that the seal on shifter linkage/shaft is leaking I would like to change it also but can not find a number for it or anyone that can tell me. the manual I have only says seal my question is has anyone changed one and is it a rubber o ring or is it a seal and if you know a seal number . I do not want to pull it without having one to replace it as it is only a drip it is a standard 3 speed any help will be appreciated. thanks in advance