If the popping sound is a backfire, it could be too rich. Your accelerator pump might be leaking into the carb throat. Float level might be too high, valve and seat might be stuck open, etc.
What's the story on the carb? Rebuilt? After shutting down hot, look down the throat of the carb and see if fuel is dribbling or pooling on the intake runner.
Ignore the ball and set the timing by lining up #1 wire with the rotor when #1 cyl is at TDC. You can put a straw in the plug hole or put your thumb over the hole or take off the valve cover and observe to determine when #1cyl is at TDC.
The BB will either line up or it won't but you'll at least know that your timing is set correctly.
The carb is a new-ish chineseium unit based off of a Rochester B. It came on the truck. It did have a fuel leak down the throat, but I put new gaskets in it and reset the float level, and it has no leaks as far as I can see.
I'll try and check the timing relative to TDC next time I'm under the hood.
You said it ran like crap due to bad gas. Drain the tank and add fresh gas. Mixing good gas with bad gas does not make bad gas good.
The gas in it was only a few weeks old, so I don't really see why it would all be bad, but it did certainly smell funky (the same smell as when I pull fuel system parts out of trucks that've been sitting in the local junkyard for a while) so that's why I suspected bad gas. Since it has been running the gas smells fine and the truck runs alright. I'm not sure if it had bad crap in the lines and the rest of it is alright, if all of the gas is bad and the truck just happens to run (ish) on it, or if something else was causing the starting issue.
