My fuel guage also shows empty all the time. The car sat idle for 10 years in a garage. The owner "said" he cranked it every month. Where is the fuel sending unit on this car? 1974 Maverick 200CI L6 manual transmission.
in the tank with the pickup. check all the wiring first. might just be as simple as a loose/corroded wire.
the sender/pickup goes into the front bottom of the tank just behind the center of the rear. start from there.
Actually, only the 70 is in the front of the tank. The rest are on the drivers side. THere is a 2 pin connector that just pulls off. Pull it off and take a paper clip and short the 2 pins in the connector together. Turn the key on to the run position. If the gage deflects to full, the problem is in the sender unit. If it still stays on empty, you have an electrical problem.