In a way, you could say I know plenty. Both of my grandparents have this disease. I lost my grandfather in 1998 to it. My grandma was diagnosed in 1999. She "had" to have some heart surgery or whatever and they blamed lack of Oxygen to it. There, I believe, are many different types and phases of this disease because we ended up having to put my grandfather in a home because no matter how closely we watched him, he was still able to sneak out the house; my grandma on the other hand is in a hospital bed on an air mattress. My dad works for a Home health Care thing and so it was very easy for us to be able to find assistance in taking care of my grandma. Yes, it is 2004 and she is still here. She was born in 1919, too. All I can really say is make your grandpa as comfy as possible. My grandma is so far gone that we can barely get enough nutrition down her, and she doesn't show pain. She takes Hydrocodone (still, I think), for pain when they had to extract some teeth that she was literally chewing away. She is in diapers and we have a nurse who comes 3 days a week that changes her and bathes her. It has been really stressful because my mom has been forced to work on weekends only now since I and my sister and brother have gotten older and are in college now (Sophomore, Junior, "Senior"). My sister still has a few more years of school before graduating and then will be planning a wedding. And, I, am soon to go off to a university and leave the Community college atmosphere.
You may want to see if your city has anything like a Home Health Care Service in which a nurse, aide, whatever, will come to the house, most likely 3 times a week, and do what is needed to help you take care of your grandfather. The service we use also has a 24 hour on call unit where if my grandma has a "seizure" they will come out and assist the inncident and do/call whatever whomever needed to make it pass. Please let me know if this helps and whatnot!