voltage regulator/tach module wiring

[rickleona]

Purchased regulator/rectifier Part #804278A12 for 2002 75HP 4 stroke Mercury. Replacement regulator does not have gray wire for tach signal as the original regulator. After many calls to Mercury customer service, I was informed I needed a harness #8042903 and tach module # 8M0026570 to enable the tach to function. Received both parts and no wiring diagram. Wire colors on tach module do not match any colors on harness or engine. Was informed by Mercury customer service that these are Yamaha parts and Yamaha does not provide instructions or diagrams for proper installation. This is totally unacceptable, I must have instructions or a diagram. Please provide!!!

[boats.net]

I don't see any instructions on those part numbers, What color wires does the tach module have?