Good pic Anton, thanks.
Thanks for the suggestions guys.
The springs aren't sided so one side points up, the other side points down.
Same with the metal bar- left and right brakes use identical bars so one has to curl up, one has to curl down. The tangs still hold it up ok though so I'm pretty sure it's ok.
The top loop of the cable should be in front of the little guide I think. This is how I'd assembled BOTH sides at first. The cable on the working (left) side though has stretched so I've moved it behind the guide onto a fatter part of the peg to tension it slightly. It's done the trick and still works.
This mod is on the GOOD side so not part of my problem.
I'll try swapping parts left to right, see where the fault goes then!
Thanks for your help

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