Chevrolet: 1994 chevy lumina sedan, chevy lumina, fuse box

Question
i am hearing a constant humming sound coming from the gas tank (which i believe is the fuel pump)is it hard to change the fuel pump if its in the tank? the car sometimes stalls out for no reason and it loses charge if not run for 2 days  the battery is brand new and the alternator is new i have noticed corrosion in the fuse box  any way to stop the corrosion in the fuse box?  please help   matt

Answer
Matt ;
Hi  the pump in the tank is not that hard to replace , look in a tech. book it will show you step by step how to do it. and the fuse box should not be getting corroded I would look to see what is causing it and fix it , is there a water leak ? try to brush off the bad oxidation and spray it with a bit of wd-40 .>>>