Re: 99 Wranger TJ fuel issue
Welcome to the garage.
Not familiar with the TJ, but lets see if i can be of any help.
Since you replaced the level sending unit already, i would not expect the problem to be there: its most probably a bad connection in the wires from the level sending unit to the PCM. ( since i donīt know the TJ, i presume that the fuel level signal goes to the PCM, but correct me if iīm wrong). So i would check the wire bundle going from the tank level sending unit going to the front for chaving or other damage and check eventually connectors and/or splices for corrosion or water ingress.
It can also be that the instrument cluster is faulty. I donīt know if you can do a instrument self test as with the WJ, but you could give it a try: with ignition switch in OFF, press the odometer reset knob and while doing so, switch ignition in run. All indicators should move full scale and all lights will be on. Odometer will count 1111111, 222222 etc.