also, be very careful taking out the fuel pump. the low fuel gauge is a long wire that requires you to put the pump at a weird angle to get it out and you do NOT want to damage or bend it in any way, shape, or form. wear safety glasses or keep your eyes a good distance away from the pump as you go to remove it, there's a bunch of what looks almost like steel wool type material around the fuel pump on the inside of the tank and it will splatter fuel as you remove the pump.
also, dont use dawn/water. use rubbing alcohol, it'll dissolve into the air with zero ill effects.
AND, it's much easier if you run the tank down on gas before you start your work. you'd be surprised how long it actually takes to drain the damn thing from near full. dont ask me how i know.