How to change a fuel pump in a Mercury Mariner?
 

I have a friend who has a 2008 Mercury Mariner and her sending unit is out in the fuel tank and I was wondering if it is easy to get to or is it one that requires dropping the tank? I have looked online and cannot find any info on doing this task. The fuel pump works she just dosent know how much fuel she has and has also just bought the vehicle so she is not real familiar with how it all works.Thank you.