Just got an 83 4x4 and had to replace the tank, truck ran before I replaced, but I think I got the fuel lines mixed up, which of the three lines are what INTAKE, RETURN, VACUUM? there is one on the right side of the frame, and two mounted under the cab on the right side of the truck, need some help...

 

i believe the line on the frame is for feeding the carb.....the line going to your charcoal canaster is for the venting line on the tank and the other line is obviously return lol, well thats how i hooked my lines back up

 

hope this helps, it is out of my '81 FSM: