Classic/Antique Car Repair: fuel gauge on 1967 plymouth gtx, 1967 plymouth gtx, chysler imperial

Question
FUEL GAUGE DOES NOT REGISTOR PROPERLY  NEW TANK  & SENDING UNIT INTALLED  GAUGE ONLY  GOES TO HALF  FULL WHEN  TANK IS ACTUALLY  FULL  PLEASE HELP AS I  HAVE  SPENT ALOT  OF  TIME ON THIS PROBLEM  ALSO CAN SOMEONE TELL ME  HOW TO SET THE  KICKDOWN LINKAGE ON A 1975 CHYSLER IMPERIAL 440 C.U.AUTOMATIC  WITH A EDELBROCK  750 CFM CARB THANK YOU

Answer
On the fuel tank when I have this problem with an older car I usually drop the tanks. Remove the sender and connect it to the circuit with jumper wires. Then with the key on move the sender arm and watch the gage. If it responds correctly then check the fit of the sender inside the tank to make sure that the arm is not binding. If the gage does not respond then remove the sender wire from the sender and ground the wire from the gage. The gage should go to full. If it does not then there is a problem with the gage.
Brad