What a pain of a day
Thought I would just replace the busted rear tail light on my trailer today - never even saw that small sign post at the child care centre

but no..........
All looked good, then no tail lights on the trailer, brakes are fine, indicators are good. Tore apart the trailer wiring and plugs all circuits are good. Then I noticed that the left rear tail light on the jeep wasn't working either. No problem I thought must be the bulb and sure enough blown. $2.50 later and the repco replacement was in place.
But still no left tail light on the jeep

Brake light is fine and its in the same bulb

Checked the fuses -

blown fuse. Another trip to repco and $2.75 later new fuse in place. Turned on the lights still no left rear tail light

And the trailers not evenin the picture at this point - so its a jeep thing.
started checking everything again and another blown fuse - and yes i did the 'must have been a dodgy one' and put in another. - turned on the lights and pop!
Now in the old CJ it would be a case of run a new cable - I replaed the whole loom a cable at a time I think

But not so simple in the KJ. I searched on here and the most likely suggestion is a fault in the rear light cluster - given the burning on the tail stop light holder I wouldn't be surprised but I swapped in the fog light holder and same problem. ( in fact what is that lower bulb for its got two fillaments?)
Now I'm thinking maybe I burnt out the trailer harness when I hit that sign. I've got a spare harness but looking at the install instructions it seems to involve removing half the back trim and the seat belts
So - anyone got the bleeding obvious anser I'm missing or do you all think this is just going to be one of those PITA things?