Re: Proper way to tap into 12VDC wire?
When I did my wiring I ran lighting to the head where I had a terminal block for lighting and mast wiring. That terminal block distributed lighting to the V-birth and Cabin and to the port side of the boat where I used another very small terminal block in the hanging locker to distribute to V-birth and cabin port side.
The small terminal blocks sort of felt like overkill but they really don't take up much space and didn't take much time to install.
That said in some places I struggled with heat shrink but splices but from now on, when it's convenient for non critical lighting I'll just twist the wires together and shrink tube them or wrap with self fusing tape. For places where but splices aren't needed I think that's fine.