1100390 was a short step down case 2 brush 12 volt 20 amp generator used on Case tractors from 1957 to 1960.
There never was a 3 brush Delco generator in a step down case. Three brush generators had the brushes mounted on the rear plate. The later model long and short "step down" cases had the two brushes mounted in the case itself and the end plate then became free of any brushes and or brush holders.
Ken
