Does any one know which connector and which pin(s) feed the
gas gauge at the instrument panel back? I just installed a whole
replacement cluster as the old gauge didn't work and I found a
replacement pretty cheap. The replacement gauge is reading
intermittenly -- sometimes no reading, sometimes I get a reading,
sometimes if I hit the top of the cluster bezel hard enough
I get contact and a reading. So which connector is loose and
needs tightening or soldering?

The reading/ohm/voltage levels at the trunk seem to
indicate a functioning sending unit.

My old gauge only worked once since I bought the car -- when it
was 100 degrees outside and I parked in the sun allowing the
interior to really heat up. I assume the heat expanded the metal
contacts enough to get contact. So now I'm guessing when I put the new
cluster in, whichever pin/wire is loose was pushed somewhat closer
to it's proper place. However, I did wiggle all the wires with
the ignition on and couldn't tell which one was causing the trouble.

Thanks for any help!