Chris,
Your "knot coding" scheme is similar to the one in our 1960 Pacer,
except we have 5 small red wires:
red, 1 knot - right brake and turn signal
red, 2 knots - left brake and turn signal
red, 3 knots - tail and clearance lights
red, no knot - separate brake lights
red, no knot - unknown
Our 1960 Pacer has the round Bargman 99 tail lights; don't know if your
'63 has them or not. If so, one possible source of confusion is that
the Bargmans have separate turn and brake light filaments, designed to
work with a separate "brake only" line, along the lines of the center
mounted brake light which is now standard on cars. It is not essential
that this line be connected since the brake and turn lights serve the
same purpose. Nor is there a "brake only" line in the RVIA standard
7-wire connector. The trailer wiring suppliers sell a little logic
module that you can use to connect the "brake only" lights to the left
and right brake and turn lines.
In our '60 Pacer that _still_ leaves one red wire of unknown purpose.
In our trailer it is connected to chassis ground, whether accidentally
or on purpose, I don't know. So far I have left it disconnected without
any apparent ill effect.
Best,
John & Barbara Sellers
WBCCI/VAC #1587
1960 Pacer
Dayton, Ohio