[JSeery]

Are you sure Skips coil requires a ballast resistor? As already stated, I would remove the two outer carbs and block off the manifold. That way you are eliminating two possible sources of the issue. They serve no purpose at this point and increase the difficulty of trouble shooting.

Also might want to put a pressure gauge on the fuel line and double check that the regulator is working correctly.

You could also pull the spark plugs and do a compression test on the cylinders and check the plugs over.