for the grandfather, I'm sure he has endured more than his fair share of people TELLING him he needed to quit over the years. Nobody likes to be told what to do. Try a more suttle approach......just give it to him as something different to try out. Maybe even wait until a couple weeks after you get yours so that you can back up the suggestion with "Ive been doing it for ...... weeks and I cant beleive (insert felt differences) how much better I ........(feel, breathe, sleep, more energy, etc). He will likely be very resistant to any sort of "quitting" method. Need to build up the fact that it is an "alternative" and not that he will be quitting his beloved 40 yr habbit.
welcome, and good luck to you and him.