Sorry to hear about your issues. We should eliminate what we can first and start with basics (I know you checked this but maybe the green and black wires got swapped)
You should see a Green wire which controls coil #2 - those wires go from coil #2 to cylinders 2 and 3
the BK (I assume black) wire runs coil #1 and those spark plug wires go to cylinders 1 and 4 (spark plugs wires seem ok? no shorting?)
The spark plug gap should be .028 with wire or spark plug gap tool (not using feeler gauge) They come pre-gapped.. did you open the gap up?
Next lets do a compression test (throttle has to be wide open - all spark plugs out.) and see what we have before we fault the carbs again.
good luck.
Lets us know so we can advise you further.
Another test is if you have one of those thermal infra red heat sensor guns to tell us which of the 4 exhaust pipes are getting hot and which are stone cold. It might help diagnose if you can get it running enough.
Also, you are a smart man to have installed overflow tubes. You probably already saved the engine from major damage.
One more thing- get rid of that NAPA filter and try the petcock on PRIME please.
Have you verified the fuel in the bowls and test the float valves (drop the hose down lower so more fuel fills the hose and then stops) with a length of clear tubing held next to the carb bowls? The fuel level should stay right at the split where the bowl meets the carb body.
https://www.youtube.com/watch?v=PHuB1lyagKMYou said this: I tore the carbs apart and cleaned them to look like new and replaced every rubber piece
I can assume you did not change the rubber diaphrams as those are expensive. Please tell me you did not use carb cleaner?
Do you know how many people have cleaned the carbs to look like new and the engine will not run... a lot~! Are you sure you cleared all the jets/orifices? Assembled them correctly? You 'really really' need to KNOW these carbs to work on them.