I'm doing a little work on the 300 we bought a couple of months back. It had the Microphor toilet with the requisite fill-when-it-shouldn't issue. Not sure why this unit was equipped with an electric one as the black tank is directly under the toilet. Anyhow, rather than dealing with it, I ripped it out and replaced it with a good ole Sealand pedal flush. Had to use the Sealand adaptor because the flange on mine wasn't lined up straight.
Pulled out the washer and compactor along with the instant hot unit too.
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