This is NOT a job for the untrained. First make sure it's as empty as it can be. Then you will need to have the car on a lift. Once it's in the air you will be able to see the bolts that hold it up. Place Jack Stands under it and lower to the jack stands. You'll need help!
It's a big deal, 'cause it's INSIDE the gas tank. Haffta drop the whole gas tank to get at it.
Inside the Fuel Tank. You have to drop the Gas Tank to get to it.
According to the 1999 Mercury Grand Marquis Owner Guide : ( 71.9 liters / 19.0 U.S. gallons )
Yes
You must drop the fuel tank.
You must drop the fuel tank to access the pump.
Inside the Fuel Tank. You'll have to drain and drop the fuel tank to change it. Not a job for the untrained!
On a 2001 Mercury Grand Marquis : The fuel tank is mounted vertically behind the rear seat
19 U.S. gallons ( 71.9 liters ) according to the owners manual
According to my Chilton's Auto Repair manual : A 1988 Mercury Grand Marquis has a ( 20 U.S. gallon ) gas tank
The ( 2007 ) Mercury Grand Marquis has a ( 19 U.S. gallon tank )
Call for help. Fuel pump is INSIDE the fuel tank. The entire tank needs to be removed to get at the electric pump.