How many grounds

g413,
Yes, that fuel sender ground strap is often missing. I think it is made of spring steel, so may rust away. Even if not, it may have an erratic electrical connection to the tubing. It is in series w/ the level sensor, which varies ~10 to 90 ohm, so needs to be <1 ohm to not affect the signal. Of course, the designers only cared if it worked for the 3 yr warranty period, by which time most buyers in those days had sold the car and bought the latest model for that new-car look - squarer body, front beak, square headlamps, ... I vaguely recall some new senders have a male spade on the outside to clip a ground. On similar note, some models (B & C bodies?) have a rubber isolator on the steering column and need a ground jumper or the horn doesn't work.