It would help to know what car this was as later model cars had a clutch interlock switch that prevented the car from starting until the clutch pedal was pushed in.

But, for all practical purposes, Ford uses 2 seperate cucuits to the starter neutral swtch whether on the steering column, floor shifter or transmission. One curcuit prevents the engine form starting unless in neutral or park and the other circuit turns the backup lights on and off.

Most after market shifters have a place to mount two micro switchs to control both of these functions. Sometimes the switches aren't include and have to be purchased seperately. You will need to find the wires that go to these circuits and extend them so they can be wired up to the switches on the shifter.
[addsig]