I'm replacing the old Grohe 47.050 cartridge in my Grohtherm 34.122 thermostatic shower mixer valve. A small packet of grease that came with the new cartridge says it's "Armaturenfett" grease which translated seems to mean "grease fittings". Where on the 47.050 cartridge should I put this? Just on the rubber seals, or all up and down the metal shaft of the cartridge? or somewhere else?? Should I use all of it?