Bart - some went on the outside, some went on the inside, with a metal washer protecting the felt from the return spring.
Tom - the new old stock WW, will have a leather accelerator pump. Prior to use, dribble several drops of light machine oil (3 n 1, neetsfoot, etc...........I use Singer sewing machine oil, my wife is a quilter) down the pump sticking through the hole in the airhorn, and allow to sit for a few hours to penetrate the pump leather. That 65 year old leather pump, if treated with the oil, will outlast 25 of the new neopreme ones.
Jon.