My guess is that the cylinders and rings have been gas-washed and you now have little to no compression.
Here's what I would do.
To prevent a repeat, I would shut that stinking electric fuel pump off. then
Fill the carb with fresh gas to the proper level, and pressure test the float valves. The engine will run for several minutes with what is in the bowls.
When you are satisfied that the Float valves are not leaking;
Install a battery charger.
Disable the ignition, Remove all sources of ignition in the vicinity, then pull the plugs out, then bump the engine over a minimum of two revolutions, to pump the gas out; put down something to protect your paint. If gas comes shooting out, turn it a few more revolutions.
Next; put a few good shots of motor oil in every cylinder, and let it sit for a minimum 15>20 minutes, to allow that oil to wick down into the ring-lands and such. Leave the plugs out
While yur waiting,
change the oil and filter.
Next, verify that your reluctor gap is set, and that the Distributor is shooting sparks when you spin it, (hooked up of course) then install it correctly at #1TDC compression, then advance it to anywhere in the window of 8>18 degrees. Leave the clamp loose enough that you later pull some timing in, if she wants more, but tight enough to not move by itself. Then disconnect it from the ignition circuit. Prove the cap is indexed, then Prove your firing order.
With the cylinders now gas-free and oiled, crank the engine over to distribute the remaining oil and or pump the excess liquids out. Leave the battery charger installed.
At this point, I would do a compression test, cuz if it doesn't start right up, everybody is gonna ask for the numbers. The numbers will be artificially high, cuz of all the oil still in the cylinders, no big deal.
If the numbers come in good, and even, then you can clean and dry the plugs, then put them back in, and reconnect the ignition. Leave the charger installed.
Verify the carb still has the correct amount of fuel in it. IE it didn't run out somewhere.
At this point, With all the cranking, the polluted oil should now pumped out, especially out of the lifters; and the intake manifold should be dried out; and, as the theory goes, she is ready to be started.
Unless you leave it overnight in a heated garage, I can almost guarantee you that, some raw gas is still gonna be hiding here and there, which is gonna cuz the engine some grief on start-up, so;
Go get your fire extinguisher, and keep it handy, somewhere NOT where the fire might start, lol
DO NOT TURN THE FUELPUMP ON .
What we are gonna do, is a test crank, so the engine can tell us what she does or does not need or want; just a few seconds.
So, disconnect the stinking choke, wire it open, and put the throttle up on the second highest step, leave it there until the engine is running, and she finishes her bucking and farting, and starts racing. While you are waiting, check the oil pressure real quick.
Ok
Ready, set, crank it! 5 seconds with a Dakota Mini starter, 10 if you have a Mopar rrrrrr-rrrrr reduction starter.
Did it start? Immediately, Check for external fuel leaks. If you got some, shut it off! and fix them. If no leaks then let it rev for a bit to push the fresh oil thru. It's gonna run out of gas in a minute or two, so just let it run at up to 2000/2500 , so she can clean herself out.
If it wants to stall right away, just grab the distributor and pull it CCW to advance it as high as she likes; up to 30/35 degrees if the timing light is still connected. Don't worry about the exact timing numbers at this point, just keep it running until she runs out of gas.
Ok but, if she doesn't start with a short crank; the question is why? and now we have to think about it.
1) Did it try? that proves the ignition system is working.
2) did it backfire flames thru the carb? that could mean that an intake valve is not closing, or there is just gas in the plenum; let's see the compression test results.
3) Did it afterfire repeatedly out the exhaust? That could mean she's still flooded and the exhaust system has gas in it. We're just gonna have to crank longer.
OR
4) did it just crank with no action whatsoever? This is actually the best as can happen, cuz it's pointing to NO GAS anywhere in the induction tract. This is what I'd like to see. In this case, turn the key OFF, lean over the carb and give it TWO shots of gas all the way to WOT and all the way back to idle, looking for a steady stream of fuel, no air. If the first shot was full of air, give her another; then put it back up on the Second highest Fast-idle step.
5) ok we're ready for a retest, this time maybe up to 10 seconds. What's happening?
Hopefully it fired right up and so, now we go back to #1 above.
If the battery is pumped up, now you can remove the charger.
6) after she is up and running successfully and has run the gas out;
a) fill the bowl again, look for fuel leaks, then kick the throttle off the fast idle step
b) start her up and check that the idle speed is adequate to prevent stalling. With the Vcan defeated, reset the IDLE-timing to around 8 degrees snug the clamp, and idle her up to 700 for now, re-connect the Vcan, then let her run the gas out.
7) Now we gotta figure out what's wrong with the carb.
Ok Hopefully I hit all the bases for ya.
