apart from very limited access,you will find that the belt tensioner is fitted into a housing on the water pump,and it sticks solid( Well it was on my 1999),so pump has to come off (usually) so you can knock it out. So budget for new pump. Should fit one anyway as its the same work to do it as the belt. Not an easy job took two of us all day. also if you do it make sure new pump is fully torqued before lifting engine back into position there is no access to bolts once engine and covers are back on so if a leak all back to start. Was quoted 300 labour by motorhome dealer if I was to do another it would go to them.