The real purpose of the buddies is not to grease the wheels but to allow for expansion and contraction when taking hot drums into cold water.(they have a spring system in them to do this) Amphicars should have front drums removed one a year to check for water in bearings, condition and brake operation, then repack the bearings, do not pump greese into buddies like you do a boat or RV.
Ron is in Fl, now and has a set of front shoes.