340 Starting issue

Evidently it sounds like you're just throwing parts in and not addressing the real problem. You never responded about fuel in the carb after it dies to pump the throttle to see if it is a fuel issue with fuel in the carb squirting fuel. You can jump the ballast resistor and run 12 volts from the battery to + side of the coil to see if it keeps running, just don't run it too long or you'll burn up the coil. It's either fuel or spark. If you're not capable of checking that let us know and we'll then tell you to take it to a mechanic. All the posts here have pretty much covered what it could be. But not physically looking at it we really can't tell exactly what you're problem is.