1953 new Yorker 5.7 hemi 545 upgrade

This may seem like a dumb question but, when it's idling and the plugs are pulled, are you just letting compression blow out and run on 7 cylinders? And is it an OE or = throttle body?
I don't think your crank sensor is bad if you are able to make it run at will. Something to consider is fuel pressure, the factory injectors require around 58 psi to operate. Most in line electric pumps don't get over 12 psi.

Sorry I just noticed this was in the Welcome wagon...So welcome, and I will repaste this when the conversation get to the appropriate section.