Hi there, I'm rebuilding my 1993 ATE brake master cylinder.
The O-ring kit I have seems to have an extra seal(indicated by tooth brush) that doesn't correspond to any of seals on the sprung assembly.
What is that for?
I've seen a couple of videos but they don't seem to cover the disassembly of the spring part.
How do I get it apart to put the new grommets on?
Any tips would be appreciated.
Having said that this repair will only be temporary as there is slight scoring on the inside of the bore.
Cheers 
