"My worrys are the fact that I read the boats should be checked every 5 yrs and replace every 10 acorrding to the sailnet articals, and yet I have a 20+ year old boat..."
I think you've got some articles confused, I don't think I"ve ever read advice to replace keel bolts on a schedule, let alone only 10 years. If it offers any comfort, in my thirty years of boat owning I've never seen a replaced keel bolt nor do I recall any other owner recounting replacing a keel bolt. I believe that bolts from reasonably conscientous builders will last the indefinite life of the boat, but I'm no engineer or expert. The keel fasteners on my twenty year old CS look no different than I expect they looked the day the boat was shipped from the factory.