[C38] masthead wiring

[Charles]

I am installing the OGM tri-color / anchor (LED) as a replacement to the 
anchor light.  The mast is currently mounted on the deck and the boat is 
of course still on the hard, which means I cannot reach the wires coming 
from the bottom of the mast.  My problem is I just removed the anchor 
light and discovered it was actually two bulbs with four wires (it 
appears that one is white and three are black, but I am standing tiptoe 
at the top of an 8 foot ladder in bright sun).    Is this normal (I am 
referring to the wiring and not my mental state:-)?    Why only one white?

Thanks,
Charles Finn
Mighty Quinn #114