fuel pump location on supercrew
 

is the fuel pump accessible under the back seat of 2003 supercrew

Take a look under the truck and you will probably be able to answer your own question.

It is on top of the tank. You need to drop the tank.

I think he was wondering if he could cut a hole in the floor under the rear seat to get to the fuel pump. This was possible on my 95 Mark VIII Lincoln. I don't think it's possible on a crew cab.

Not sure, but if you don't drop the tank I think you have to lift the bed.

As far as I know this is correct. Most people drop the tank because the bed is pretty heavy and awkward to take off the truck.
The fuel pump is inside the tank.

Axiom: Fuel pumps almost always go out right after a full tank fill up!!

It's funny, on my Jeep Compass, you take the rear seat out, remove access plate, remove electric connector, get a brass punch, tap,tap,tap, turn the slide ring off, remove fuel pump, then reverse install. 20 minute job.

On our trucks, we need to drop the tank or remove the bed. You'd think they'd make an access plate...

I did s fuel pump replacement a few months ago.
only way in is to drop the tank. FYI if youre goign to change the pump, replace the inline fuel filter at the same time.
Start with the filter. it will clear out most of the fuel in the line before you start on the tank.
IF youre unsure of what steps and tools you need see if you can find a junk yard nearby. you can walk thru the replacement without worrying about messing up on your own truck.