On Sep 21, 10:51*am, Ignoramus17765 ignoramus17...@NOSPAM.
17765.invalid wrote:
The trailer that I bought, has electric brakes and electric lights.

The lights worked intermittently, such as worked only once or twice.

The electric plug is a two piece job, with wires held by screws, some
wires fell out. Not good enough.

I bought a replacement molded one piece plug with 8 foot tail, and
will use it. What I want is to do a good job rewiring the trailer. I
believe that the trailer body is used as negative ground, which is not
so great when there is corrosion. So I want to be sure that I follow
"best practices" and to know what they are.

Any suggestions?

i

Do NOT use the vinyl covered wire sold for trailer lights!
The vinyl attacks and corrodes the copper wires inside, and will turn
into junk in a few years.
Use 16-3 SO wire, a separate wire to each light, and use one wire for
ground, and one for tail and one for the signal light.

Never use the frame for a ground. Total waste of effort. over the next
50 years..