Onan DYG Series Operator's Manual And Parts Catalog page 54

VOLTAGE REGULATOR GROUP - KEY 1,2,3,4,5,6
S P E C A THROUGH C
2 2
7 - 8
1 4 - 1 5 - 1 6 - 1 7
1 8 - 1 9 - 2 0 1 4 - 1 5 - 1 6 - 1 7
52