Fuel guage sending unit ohms range

[phlorentz]

I have 1989 Grand Wagoneer with a custom fuel tank. I need to get a sending unit that matched the ohms range of the sending unit. Does anyone have a manual that shows the testing of the unit or the ohms range? I have seen several ranges listed in different places so they cannot all be correct. Maybe someone has one that they could test the range. Thank You