Fuel pump on my 1976 454 is ON the side of the block—and costs $26. Takes about 1 hour to R & R.
The fuel pump is inside the gas tank of an F-250, as you no doubt know, and apparently the fuel-level sensor is built into the pump. So far, the pump itself works fine but the check engine light comes on if I get much below a half tank, then resets after filling up. Not worth dealing with yet.