Fuel Gauge always shows empty

see if there is any acces to the fuel tank cover under the rear seat, if it is then remove the screws and remove the sending unit sending unit inside the tank most likelly it will be bad, but if you don't feel like doing it, then take it to your mechanic but seems to be the sending unit inside the tank wich is the sensor trigering your gage is not good and need to be tested and replaced

One of two problems. Float on righthand side sensor catches on the tention beading ******** tank. Remove and bend arm to cure problem.
Secondly, resistances on sender units in tank are out of speck. Check resitances with ohm meter. Each indiv. sender should read 5-250 ohms. (zero to full position)