Thank you - I wasn't sure what you were referencing. I think (hope) I'm starting to understand this a bit more.
Can I use the frame as the negative path in place of the battery to charger cable? Is this considered beneficial/safe/recommended/worth the effort ... etc, etc.? If yes, I could easily take the negative 6awg wire and pair it to the existing 6awg positive and get some short "large" gauge jumper wires to go from battery to frame and frame to charger. Not as good as the 00awg but it's closer than what I've got right now.
About moving the charger/converter. I'm sure I could but ... I'd have to get/make an enclosure for it since the circuits are exposed (it's a drop in for the WFCO unit) and I'd need to run a 120V wire & outlet to the front, where there is no 120V anything. In the long run, I think it'd be easier to run new battery cables ... my opinion.