It's not that difficult. Just a matter of taking the screws out from the trim plate inside the pool, taking the old skimmer off, replacing the gaskets, put the new skimmer in place, and screwing the trim plate back on. You might need an extra set of hands to hold the skimmer in place while you get a few screws started, and depending on how tall you are, you might need a stepladder to be able to reach over the top rail to get to the trimplate.