This is a car repair I would suggest taking to a mechanic. If you are very comfortable doing vehicle repairs, get a Haynes manual and take a look and see if you think you have the tools and ability to do it. I have that ability and I would rather have a mechanic do it. Often water pumps are located in/on the engine blocks and may be connected to the cam or the drive shaft and you may need to take significant amounts of the engine apart, often you may also need to time the vehicle after the repair, so I just take it in.
