What ignition system and what brand and part number spark plugs are you using?
Where do you live and how much moisture is in the air where you live?
How old is the gas in the tank your trying to use?
I've had issues like yours with starting with old dead, no octane and won't evaporate properly, gasoline.
I buy 100 octane low lead aviation fuel at my local airport to use in the cars I have that don't get driven much, that fuel has a 18 month shelf life so it doesn't go flat, bad, as quickly as todays pump gas shruggy
On the Holley carbs I will fill the fuel bowls up with fresh fuel with a syringe so the motor will start and run for a short while on decent fuel and put some heat into the motor to help it run on the old fuel in the gas filter and fuel line and tank.
You may need to drain the gas tank and fill it with new gas if your gas in the tank is more than 6 months old and you live in a area that gets above 80F during the spring, summer and fall work twocents
I have a 1969 Dart GTS 383 4 speed car that I haven't driven in the last two years so I'm facing the same deal this year as your dealing with now shock
I did fill it with 100 LL but it has sat for over two years now, I have started it and moved it a little but no trips of any distance, less than a mile in our neighbor hood and driveways luck
BTW, it is illegal to use leaded fuels in this country on normal street vehicles tsk

Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)