If replacing the obsolete mechanical regulator with a new solid state regulator on a Yanmar YM1600, YM1900, YM2200, YM2700, or YM177

** Looking at top of your old original regulator you will see terminals Left to Right IG, A, F, L, N.

** Looking at the VR-550 plug- terminals facing you, narrow end (notches at the top) of plug up- Upper left to right - N, A, L, Lower left to right E, F, IG. " E"- Is attached to ground post on alternator.

Regulator Is Found HERE