Fuel pump replacement.
 

Hi there.
My 91 w150 is having fuel gauge problems. It reads past E when fuel and then moves up later and when it has 1/2 a tank it really has 3/4. I'm assuming it's the sending unit because it is to consistant to be a wire. So back to my original question. How do you change the fuel pump? I've heard a mixture of things from just dropping the tank, lifting the bed, and cutting through the bed. Which is right? I hope dropping the tank because I've done this before on a Ford and it was rather easy.
Thanks for looking.

All three will allow you to get to the top of the tank. Dropping it i believe is the best way.

Thanks for the info.