Fuel gauge not working 94 Ranger

The fuel gauge has stopped working on my 94 Ranger 3L. It was fine until I filled up with gas and it never moved from near empty.
It flickers a bit when you turn the key on and off. I have no Idea of the fuel range of the truck as I have just bought it.

you can figue to get abt 200 miles safely. sound like a replacement of the flaot in tank is needed. try checking wires on top of tank first before you remove it. corrosion could be your problem