The fuse panel behind your flip up instrument panel is the chassis fuse panel.
The 12 volt house fuses will be in your power control center. Usually behind a drop down door with vents below and often in the kitchen area on your vintage MH. This panel contains your converter, 120 volt ac breaker panel and the 12 volt dc fuses for your house equipment. These are the main 2 fuse panels for Winne's back then. Of course, there could be other inline fuses and breakers for installed accessories.
Good luck.
2007 Itasca Suncruiser 35L
2000 Jeep Wrangler