How hard is it to change a water pump?

I just bought a 1989 Stratos 201 with a Yamaha 2.6l V6. The water pump is pumping, but when I run it for a few minutes the alarm goes off. The boat has sit for 1 1/2 years, so I belive I should change the pump. Is this something a weekend mechanic can do? if so is there some place that I can get step by step instructions? Thanks for any help.

I don't think it will be too difficult. I haven't ever done a Yamaha (and I've owned three of them). Do a search for water pumps on this page...I think someone has given some good instructions a few months ago.

Buzz you are right but don't remember when.