"183.425 - Conductors: General
(g) This section does not apply
to communication systems; electronic navigation equipment
; electronic circuits having current flow of less than one ampere;
conductors which are totally inside an equipment
housing; resistance conductors that control circuit amperage; high voltage secondary conductors and terminations that are in ignition systems; pigtails of less than seven inches of exposed length; and cranking motor
From the above Coast guard rule
pertaining to wire size and type, I concluded that smaller wire than 16 gauge could be used for powering my small LED lights
and still be within the rules.
I used an individual (2 strand) 20 gauge wire between a Blue Seas fuse block and each light fixture. The light fixtures draw about 0.1 amp so a 0.5 amp fuse protecting each wire is more than adequate to carry the load.
Certainly, a 0.5 amp fuse will blow long before the conductor or the wimpy pigtail on the fixture catches fire.