I don't think the outside panel for the Hot Water Heater has changed in years. Our 91 Prowler had the same panel as our current 2010 Montana. I think the only thing that has changed is the twist latch, from metal to plastic.
2018 Silverado 3500HD High Country Dually 4x4 Duramax/Allison, 2016 Redwood 39MB, Disc Brakes, Mor/ryde IS, Sailun 17.5" H tires, 5.5K Onan, Dual ACs, auto level, auto sat dish, stacked washer/dryer, residential fridge, King sleep number. Michelle & Ann