I need your help here guys. Couple weeks ago I bought a 1986 Dodge Ram 50 2.0L w/ 90k miles as a project truck. It started and drove fine but i never drove for extended periods of time. Finally finished up the interior and wanted to begin to actually drive it. Took it out for a drive and it ran fine then just randomly shut down. After filling it with gas as I thought was the problem it would not start. After about 30 mins it started up idle fine and then shut down again and would not start. Next day again started and ran fine and after like 2 mins shut down. Below I will list all that i have replaced and all tests conducted with the help of threads on this board. Insight will be greatly appreciated.

Replaced...
Ignition coil
Wires
Plugs were recently changed by previous owner
Disty cap
Rotor

Tests...
Carb gets gas
Coil + & both sides of resistor gets 12v on Acc and start
Coil resistance within spec
Resistor resistance within spec
Pickup coil resistance within spec
No spark at plug wires
No spark out of coil
Coil when manually grounded has spark output

Ok guys my theory is that the - side of the coil is not being grounded by the distributor so it does not generate spark. Now being that the pickup coil resistance is within spec does that mean its good or is there still a chance it is not? Also is there a way to test the igniter that's in the distributor? Is this done by checking resistance too? I did not see any mention of testing this type of igniter in both the manuals i have been using. Thanks guys and if my theory is wrong let me know or nay other ideas. It pains me to not be able to drive it.