93 Fuel Pump

Okay. Today i was driving around, when i heard a weird noise. I couldnt figure out where it was coming from until now. It sounds as if my fuel pump is starting to go. It gets really loud in the interior when the car is running, but not as loud outside the car. I was wondering. How difficult is it to change the fuel pump on a 93 Cavalier (4 door)? I took the spare tire out of the trunk and i saw a rectangular black cover which was glued in. It have a feeling it might be the fuel pump under it, but i'm not quite sure. I want to know that it's the fuel pump before i start peeling it off. Does anyone know? How easy is it to change it? Simple? I know basically everything on my cavalier has been really easy to fix sofar =D except for my transmission. Which is goin in tomorrow to see whats wrong with it.

I believe the fuel tank is under the rear seat, I know it is on a 2 door or convertible. It's not a terrible job, just use plenty of PB Blaster on all the bolts so they don't break when you try to remove them.