So, i fitted the new discs and the FD callipers today. absolute piece of cake to do, even though the pipes did need a bit of a twiddle.
What a funny set up all that gubbins is thats inside the bells of the discs.
I found the other brake pipe on the back of the hub and thought, "Eyup, what do we have here then?"
Still none the wiser but just put it all back together