318 No Start Backfiring Through Carb

I would first check that the rotor is pointing in the right direction. It is either on or 180 degrees off. Very simple fix, one bolt. If it were me, I might just pop the cap off the distributor, remove the hold down bolt, pull the distributor up about an inch, rotate the rotor 180* and reassemble it all. Seriously, it takes less than 3 minutes. Try starting it again.