So the other day, i was taking apart the dash because the needle on the gears was broken, and i had to take the fuel tank switch off. when i tried to move the truck it wouldn't start so i took the switch and put it back on. and after i parked it, i could see gas dripping from the rear tank. and didn't know why. there was less than 1/4 of gas. after i switched to the front tank it stopped leaking. But the front tank doesn't work, most likely the pump is bad.

Why would it leak?
Did i ruin seals/pump?

 

Sounds like a problem unrelated to your working on the dash.

I would guess a leaking fuel line, possibly the return line connector is broken, but thats just a guess.

Ford rear tanks sometimes rust a hole in them, but its usually toward the top/middle of the tank, so if your fuel guage is working correctly thats probably not it.

Only way to know for sure is to drop the tank.