Had an '84 pontiac that I chased a low speed miss on and finally took it to a guy who rebuilt the carb. Still had the miss when he fired it up again. Turned out to be the fuel - the car did not idle on cheap ethanol blends. Tank full of Exxon was all it needed.

I would be sure of your basics - plugs, base timing, fuel delivery, etc before chasing mechanicals. You may have already exhausted all of those, but you did not say...