I found a manual for Yanmars from some company on E Bay for $20 and bought one. It is designed for do it yourselfers with very clear instructions and photos. I can''t recall just how detailed it is in regards to winterizing, but I think it is worth having along. It does do a good job explaining how to do an oil change. I''d check for you but it is up on my boat which I won''t be visiting for a week or so. It is not the factory book, but for people like us it is probably better.
For oil changes, I had been using a par hand
pump. the kind with the brass body. It took a lot pumping to get the oil out. This year, I decided to try a new system by Tempo. It is a cannister. Once the tube is inserted in the dipstick hole you
pump the air out of the cannister and then go do something else while it sucks the oil out. When it is done, disconnect the hose and take the cannister to the recycle tank. I have used it only once and was impressed.