Whether or not a march fuel gauge will fit a B13 tank depends on the size of the march gauge. You should be able to find a march gauge that will fit on a B13 tank.
The fuel tank pressure sensor is for the EVAP system. It has nothing to do with the fuel gauge sending unit.
check for a damaged fuel tank
A gauge for measuring fuel in a tank.
Bad sending unit in the fuel tank.
signal from the sensor inside the tank to the gauge
THE FUEL PUMP FLOAT HAS GONE BAD OR THE GAUGE NEEDS TO BE CHECKED
A faulty fuel gauge sending unit located inside the fuel tank would be the most common reason
if you put gas in the tank the gauge don't work what is the problem Probably the sending unit in fuel tank is corroded. Either replace unit wit a new fuel pump or try pulling pump out and cleaning crud from float unit and sending unit and the contacts. Fuel pump is in fuel tank
Most likely either a bad float in the fuel tank or defective gauge
It sounds like you have a bad fuel sending unit. It is located in the fuel tank and the tank must be removed to replace it.
fuel sending unit located in the tank is probably bad