"The wtc will be 4"O.D. x 3.75" I.D. x 48" length."

How much of that will be ballast tank(s)?

"Three watertight compartments are an advantage."

How?

"I want to keep all of the wiring within the wtc."

How will you be able to do this if there are 3 separate WTCs?

"The compartments will have their own receivers/battery packs and be able to communicate with each other."

Boy, are you a glutton for punishment! So each time you're going to run your boat, you'll be completely disassembling everything to charge 3 batteries?

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