Won't Start need advice, Please read....

I adjusted the idle screw and the car idles. so the car starts and idles. The issue I have now is as soon as a load is placed on the engine it misses and bucks and doesn't run well at all. So far I have replaced the following:
re-manufactured carb
resistor ballast
condenser
spark plugs and new wires
coil
fuel pump
rotor

Thanks to all who comment as I really appreciate all the help !!!!