I have a customers boat here, cowling is XR 6, transom tag is 0D2328220.
It has the 40 amp stator with only 2 yellow wires, and the big single voltage regulator p/n 18736A8.

However, the drawings for that model have the 4 yellow wire stator and dual rect/regs.

This engine, according to drawings for the other model listed in the Title above, is a 1991 year at latest.

I'm wondering if someone changed the components and took the stator and dual regs off and put this one on with 1 reg and 2 wire stator.
If not, then Mercury really screwed up this transom tag lol and put a "D" instead of a "C".