The problem here is trying to tie the headlight to the engine dieing.
However he wired the sensor should not have let the engine run and then die when the headlights are turn on.
It sounds to me as if the computer grounds at the body ground are getting their ground through the headlight bulb and back to the NEG post of the battery. When the lights are turned on you kill that ground and then the computer has no ground and stops the spark and fuel.

Here is the only connection I can make that would do that is in the diagram below:


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You could start the engine then unplug the safety sensor and turn on the headlights.
If the engine dies, then you will know it is not the safety sensor.

 

How bright are the headlights when you turn them on with engine running(till it stalls)? I don't think the headlights are being used as a ground. With the headlight switch off, the headlights will be floating on that switch(not grounded on power side). When the switch is on, power will flow through the switch and headlights through the ground connector.

Unless some wires gotten shorted together or mung up by previous owners. The problem is probly right where Bill has said.

 

With the ground for the small wires lost at the body ground the diagram below shows a ground path in red that the ground could take from the computer to ground with the headlights off.
When the headlights are turn on the ground path in red will no longer exist.

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Just a reminder. In 94 ford swapped all wiring on that transmission. So if you are using a newer harness it will not work.

 

the 93 solenoid pack was installed so that is not a problem. Some of the grounds were removed and put back during work. In the process of checking and cleaning all the grounds

 

That was 1995 and not 1994. 1993 and 1994 are the same.

 

Ahh, the 2nd schematic shows better detail of the filiments of the bulbs than the 1st diagram. Yep that is more than likely what is occuring.