Key West
Regulator / Rectifier changeover
1987 Yamaha SRV 540

The overall project space.  Motor removed for case seal work.  Reg/Rect, installed, is the blue box in the lower right portion of the picture.  This is a pull start motor - no pre-existing 12V DC power setup.  Existing power is AC with a voltage chop at 12V.

The original device - it simply dumps excess voltage to ground (in excess of 12V).

Original mounting holes - too close for the Key West

Space exists for the new unit so a third hole is drilled.  The middle hole will go unused.  The project is such that the original wiring and devices could be plugged in without re-work.

Final installation
Top two posts are for the incoming variable voltage AC.
Bottom two posts are for the outgoing, near constant, 12 volt DC power.