I have a 35KW, three phase Onan with the 4B Cummins and an 85-gallon day tank, with another 350 gallons ready. Got rid of all the Onan boards and rewired with a new AVR, governor, simple relays and controls/ safeties. Extra filters, oil, belts, water pump, starter, all electrical components backups are stored in Ferriday bags. My load bank is a filled 55-gallon drum with 6- 5KW heater elements connected to a small breaker panel to vary the load.