You may not want to hear this but these guys have given every bit of info that it takes to make any engine run. If it is properly timed, getting spark and good gas it has to run. It has to be either a bad replacement part or bad fuel. I think you have to go back and look at everything again. I had a problem with an engine running fine until you dropped it in gear. I changed the converter, carb and distributor and still had the same problem. It turn out that the electric choke wire was connected to the power for the coil, reducing voltage just enough to give me fits. Maybe yours will be something as simple as that.

I once had to start an old (pre 426) hemi that had not run in years. We pulled the plugs, oiled the cylinders, spun it over to distribute the oil on the rings, installed new plugs and got it running!
Of course, we were lost in a fog bank for a few minutes, but it ran and re-started for the owner to drive it away. It had been swapped into a '51 Ford pickup and once it went away I never saw it again, thank you very much