Put a new baffled tank in my 1980 FI Spider. Tank came with new sending unit as well. Everything was installed correctly, and seemed to be working fine (e.g. wires correctly attached), but I am not getting a correct reading of fuel in the tank. When tank is full, the needle rests about 1mm to the left of the "Full" indicator, and when about 6 gallons have been used from a full tank, the gauge reads that tank is empty. Is there something about the orientation of the sending unit that I am missing??? The gauge definitely works, it just seems to need some calibration. Thoughts??

Your rod have to be lower. Bend it