Not sure if it would work on a T100 or not but instead of dropping the tank we used to unbolt the bed on the tank side and loosen the bed bolts on the other side. Then using a floor jack and a piece of wood lift to give you enough room to work on the fuel pump. No need to empty the tank or disconnect lines! If you go this route make sure you watch the back bumper, it can scrape the bed as you jack it up.

I have only done this on Fords but imagine it would work on any pickup.

Mike