No spark no start!

Looks like the lean burn is gone by the distributor. First you need to get a factory service manual (FSM) My mopar has some for free. Next pics of the ignition system and the carburetor to make sure the ignition conversion from lean burn was done right. By what you have posted almost sounds like a dirty connection somewhere but need to start troubleshooting the system.

Service Manuals – MyMopar