I use Smith gauges in my car and the fuel gauge reads 3/4 with a full tank. Obviously, that means when at about 1/4 tank I read 0/empty and have premature fill-ups. This is not a big deal around town but on extended cruises with gas up a little less convenient and assessable it can become a nuisance.
The tank in my car is a'68 Camaro's and I'm not sure exactly what sender it uses. If you have any other questions I'll try to find the answers. Thanks for your help!