I'm still driving that same truck, 95 1/2 4x4 300 6cyl. I'd bet that its the PIP sensor on the bottom of the distributor. I went thru the same issues. Removed and replaced the sensor on the bottom of the distributor and everything's been fine since. It's called a Hall effect sensor and when they start going bad you get no fire to the plugs. Here's a pic of one.
http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_Distributor-Pickup-Assembly-BWD_5240786-P_200_R%7CGRPTUNEAMS___#
You can pick up a cheap OBD 1 scanner off Amazon that will help pin point what's wrong.
http://www.amazon.com/Equus-3145-Ford-Digital-Reader/dp/B000EW0KHW
