Does the car start and run? If it does the tach has not burned open so H Code is right. If tries to start until you release the key from the start to the run position you probably have a problem with the tach or tach wiring. The tach is in series with the run circuit (not one of Ford's better ideas). If the meter movement in the tach sees too much current the coil in the movement burns open and the car with not run. It will start as long as the key in the start position because there is a splice connection at connector C-216 (the gauge feed harness connector at upper firewall, driver's side). This is wire number 16 and is red with light green stripe. The power is provided from one of the two small connections on the starter solenoid as long as the starter relay is engaged (the key is in the start position). The tach side of the circuit has a current limiting resistor wire as part of the circuit. The wire number is 16. It is a small diameter and is also red with a light green stripe on it. It provides power to the coil when the key is in the run position. To test, use a voltmeter to check for voltage with the wire (red and light green) removed form the "BATT" small connection on the coil and the key in the run position. If you have voltage the tach is not open. Sorry I've become long winded. Just trying to help.
Chuck