Oh the fun of guessing

NOG, much as I love her, has several weaknesses. One of the most annoying of these centers around the fuel tank. The fuel gauge has never worked. The wiring is fine, the actual gauge works, but I've had a succession of dodgy senders. The original was notable for being rusted solid - the previous owner had spent quite a bit of time on the rest of the system, with no success, much to his bafflement. Yours truely, being tad more canney, replaced it with a spare which refused to work (twice). I've currently given up, presuming I need to actually pay for a new sender, and being rather skint. The lack of a gauge wouldn't be that bad in and of itself - I ran Bitsa for nearly a year with no gauge - but to compound matters, the tank leaks from the outlet pipe gasket when full. Que a certain degree of panic at intervals at filling stations, particularly when I've used less fuel than expected.