Isuzu gas tank question

I know this will probably sound dumb, but is the part that is inside the gas tank only a sending unit or is it a fuel pump too? I was just wondering because my dad's went out and the truck wouldn't run. We replaced it and everything was fine. This is on a 89 isuzu with a carb.

is it a 2.3 or a 2.6 i know on the 2.3's the fuel pump is on the carb and the sending unit is on the side of the gas tank (at least thats where mine is it where all the wire hook up to) i really just wanna know how the hell to hook up a fuel cell

I have a 92 2.3 and my fuel pump is in the carb.