Explanation on Brake/Lights wiring???

I have a 66' CJ5 and the wiring for my brakes melted the other day. I'm trying to re-wire the breaks and wanted an explanation as to how it works. On my rig, currently I have the wires from the rear break lights coming down the inside frame rail and attatches to some sort of wiring plug with 4 female ends that plugs into another plug with the male ends. (I can't find this part???). One of the wires coming out of the male end of the plug goes into the turn signal box on the steering column. The other goes to the light switch. On the master cylinder, there are two prongs with wires connected and one is headed to a junction box on the fender and the other is headed to the turn signal box. Can anyone explain to me how the break lights get power when the break is depressed and when just the lights are on? and where I might be able to find that harness as I need a new one?

 

Power begins at the headlight switch where the circuit breaker attaches to the switch. That wire will go down to one of the terms on stop sw (either one) and the other wire from stop sw will go back up to the turn sig sw. The turn sig switch handles the cancelling effect for the tail/stop lights on rear only. There is no stop function for the fronts. only marker and turn on fronts. When you are making a left turn, the turn sig switch will make the brake connection thru the t-sig sw to the right side only. When the t-sig-sw is in neutral position, it makes the connection to both left and right and that is why the stop and turn portion of the tail light share the same wire up thru the t-sig-sw. Sometimes viewing the diagram is confusing unless you know how the t-sig-sw does its job. HTH