The colors dont look like the match are there any more splices?
How long is this jumper wire? I am having hard time following this wire.
The yellow/white is the signal wire for the gauge. To test the truck side wiring/gauge, get a 150 and a 15 ohm resistors from Radio Shack. Place them between the yellow/white and ground. 150 should read just over full and 15 just under empty. This is about the only way you can see if the truck works and that this jack wagon repair is wrong.
Also that pump looks like it is the wrong one for the truck, a direct replacement does not need jumpers.
99 x-cab 4x4 4.0l auto
mods, cranked t-bars, silencer delete, k&n drop in, Rebuilt trans ,Trans Go stage 3 shift kit, 3200stall Fuddle Racing Torque Converter,
VANIR 63mm TB, Roush split rear exit exhuast, E-Fan, JBA Headers
Auto up/down both windows, OHC, EATC (soon to be modded)
03 Crown Victoria Police Interceptor