I've seen quite a few of those threaded access ports (the "deck ports", but I didn't know they were called that) in larger trailers to provide service access to plumbing. If they're big enough for this purpose and the installation area is flat, I think that's a great idea; the frame of the port should provide the required reinforcement.
1979 Boler B1700RGH, pulled by 2004 Toyota Sienna LE 2WD
Information is good. Lack of information is not so good, but misinformation is much worse. Check facts, and apply common sense liberally.
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