Car dies if I’m not giving it gas...

I think the problem was probably just the fact that the engine wasn’t retaining enough heat with the headers and it just hadn’t warmed up enough and was dying because it was too cold. I drove it again with my dad a few days later and it did fine. We also cleaned the carb and I think that probably helped too. Thanks for all the input. I really appreciate the help from all you guys who know what you’re doing so I can have a chance to fix it myself and learn something about these old mopars. I don’t get on here as often as I should.