"In other words the feeder pairs have been crimp connected to the wire run inside the wire bundle (instead of at the outlet j box) "
I'm going to suggest that that would violate most electrical codes if done on land, and it is the sign of a homebrew job on a boat. We make AC connections inside of boxes as extra protection against wiring
problems, and if you have any reason to think the AC wiring
was not done 100% correctly...It might be simpler and safer to remove it all and rewire it.
Among other things there should be a double breaker on the AC main panel, and a GFI (whatever you prefer to call it) as close to the AC feed into the boat as possible. If you don't see these things--consider rewiring from scratch, instead of banging your head
trying to figure out what the last guy did.