Three weeks ago, while modifying the cabinet door mounted below our oven (conventional), low and behold, way in the inside back corner of the cabinet I discovered a duplex AC outlet. My first (and only) thought was that this would be the power outlet for a microwave if our trailer had been so equipped.
Our Hi-Lo is a different model from yours, but they may have set it up similarly.
1967 17' Hi-Lo Bon Voyage (1967-1969)
1969 19' Hi-Lo Bon Voyage (1969-2011)
2004 27' Hi-Lo TowLite (2010-present)
2015 Chevy Tahoe LTZ