Ok, it used to be very infrequently (say once a month or so) but has happened three times today already

It seems to be an electrical issue as it dies without any stumble or advance warning. Doesn't seem to matter if engine is cold or hot.

I can it in neutral, fire it right back up first attempt, it back in gear and go.

I haven't tested a darn thing so I am hoping that a guru or two will tell me what the most likely cause is so I can replace the part before Saturday.

Have you looked at the power wire on the ignition? If it's loose in any way it can do that. You are still carb'd right? What about looking in the dizzy to see if the condenser wire is still screwed down. Push the coil wire back on nice & tight on both the coil & distributor cap. Check the connections on the ground cable on your battery. Make sure that both battery cables are in good shape. Try those.

Does anything else die (radio, gauges, etc) when the engine quits? If not it wouldn't be a battery cable or ignition switch problem.

What type of ignition system is in it? Does it have an electric fuel pump? Does it get more frequent when it is hot outside or cooler? I would check all connections as previously stated before going any further.

Checkout the ignition harness connectors. It's common for them to crack.

It's your rig telling you to put that damn EFI in

I'd check all the conections on the ignition switch. And all the connections on the duraspark system. My bronco just up and quit one day and what the issue was actually too much dialectric grease in one of the connectors.

Check your rubber fuel lines for any leaks, if it is sucking air in through a line you wont even see a leak, but it sucks in air when driving, dies then will restart once stopped. Just another thing to check.

Please keep the suggestions coming...........

Given that I have been fooling around under the dash installing CB radio, upgrading wiper switch, and cig lighter......I am thinking the ignition switch wiring could be the culprit.

I checked the connections and they are all tight but maybe a fragile wire is giving up the ghost.

The pdf I posted above will give you some things to check out.

Check your plug wires too, make sure they aren't grounding out against your headers or something. That's a shot in the dark as it seems you are pretty well handled, but easy to check.

J.D.

UPDATE:

I haven't had time to do any testing of the wiring, etc other than to ensure that wiring connections are tight.

Happened again this morning when I left the house.........was only going 10 - 15 mph, engine cold (but running smooth as always), and it died.

This time I didn't it in nuetral or try to restart.

I looked to make sure the dash lights and heater fan were working and suddenly it fired back up on it's own.

It was 1 - 2 seconds max between dying and restarting.

Any more ideas with this new information ?

Really sounds electrical. Got to be ignition related.

My first thought is ignition related too. I'm gonna think out loud for a few so bear with me.....
What about the starter solenoid? Have you ever replaced that? If a coil goes bad (I've never had one go out) it won't keep firing up, but if the starter solenoid goes out, sometimes it will cut in and out. A rap on it with a screwdriver handle sometimes takes care of it. I would say it has to be a loose wire somewhere. Check both the + & - wires on the coil to be sure the connection is good. It has been so long since I have had electrical issues, I forget what to look for and where to start

Good news is that with a carb motor, there isn't nearly as much to track down and trace.

just a thought i don't know if you have thought of it but i once had someone put some trash in fuel tank it would run fine tell the piece of hard plastic would suck down over outlet motor would die i would turn key off to restart it would float up and would start right back up took me almost a year to figure that one out. good luck!