1968 barracuda temp gauge and fuel level inop

Oil pressure gauge is fine. working great, as is the ampmeter
The OHMs on the multimeter set to 200 again, in the ohms setting is only gong to like 1.2 ohms with the multimeter black grounded, and the red going to the sender post with the wire unplugged and the key in the on position.
I am prob. doing it wrong, and if someone can explain how to test this for a "dummy" it would be helpful. I feel like im doing something wrong.

also the fuel gauge is still inop...I tried to ground it out to the frame to no avail. I see the ground strap on the fuel line, It looks fine, a little coroded so I cleaned it as best I could, still nothing.

What a pain in the A$$