“fuel gauge may not be accurate”
I’ve owned couple of $100 cars where the fuel gauge didn’t work. Just keep track of mileage if that gauge works. It was fine except for my dirtbag room mate at the time siphoning a full tank of gas for his vehicle and maybe a friend’s vehicle.
I had a ‘66 MGB and the speedometer oscillated like a metronome. I would average the low and high numbers of the range to estimate my actual speed. Every now and then I’d drive by one of those radar billboards that shows you how fast you’re actually going, and I was (pleasantly) surprised at how close to accurate my technique turned out to be.