If the other gauges are working, I doubt it's a fuse. There are a couple of ground lines, though, so check both. You should also check the resistance at the gauge plug (I don't have it for the NAS - sorry). The tank must be dropped to remove the sender.
"Every normal man must be tempted, at times, to spit on his hands, hoist the
black flag and start slitting throats." - H. L. Mencken