I don't know about the Bigfoot
19' specifically, but usually RV toilets use mounting flanges just like a home toilet, so if you can find them there are likely two nuts at the base to remove to free the toilet from the tank-mounted flange.
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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