[Nickelcharlie]

A neighbor down the street was having this same issue and he gave up and sold his truck to a friend. His friend that bought it fixed it by spraying contact cleaner on the wires coming in from the ignition switch and all the contacts on the cap where these wires plug into (the little square box on the side of the distributor). He has not had any problems since.
Mine was doing the same thing and I sprayed Deoxit D5 contact cleaner on mine and I have not had any problems as of yet. If it happens again I have an older model distributor I think around 68-73 that I am going to switch out with the current distributor. The older models do not have any parts underneath the distributor thus eliminating pulling the distributor out to change out parts.
Also a mechanic recommended that I use nothing but DELCO parts. I put a new off brand module in mine and it would start and run but on the highway it would miss. Took us for ever to figure that out because most of the time when the module fails it will not start.
These trucks are getting older and electrical contacts are beginning fail becasue of corrosion.
I bought Deoxit D5 on line. It Improves Metal to Metal Connections and Contacts as advertised on the can.
I also bought a can CRC 2-26 contact Lubricant, makes the connectors slide together easier and helps keep moisture out, so I was told!
Hope this info helps some one!