Need to replace fuel gauge sending unit on Sebring

[GNRick]

My gauge on my 2002 Sebring is dropping to empty then back to 1/2 tank. My mechanic says I need to replace the sensor that attaches to the fuel pump hanger. He says to remove rear seat which allows me to access the hanger. Sounds a lot easier than dropping the tank like on our Buicks. Is this very difficult to do? I ordered the sensor at the dealer. It was $77. Thanks!