Fuel sending unit

About 9 months ago, I installed one of these aftermarket fuel sending units from ebay for a 1967 Plymouth Valiant. At the time I thought that the new unit would come with a new ground strap. It didn't. So I created another type of ground which worked for a few months. Then the gauge stopped working again. I bought a ground strap, and from there the gauge would work sporadically. I've cleaned the connections between the sending unit and the gas line above the rubber hose. Now I get nothing at all.
I checked the continuity of the sender wire and it is fine. I also created a "good" ground and still nothing.
After all of this I checked the sending unit with an ohms meter. It read 0.00 everytime. As I released contact from the terminal, I would get a flashing of an ohms reading. But with solid contact. It was always 0.00. I would have to think that the sending unit is bad, even though being 9 months old. The wiring going to the sending unit seems to be good. My only thought is that it is the sending unit itself is bad. Please help with any suggestions. Thanks.

jimmys67