[Fot] Help Me Obi One...

[Ken Suhre]

 "Whats a
poor boy to do?"

Nick,
  I just happened to have the latest Moss Motors catalog lying here next to my keyboard. What I decipher from scanning page 57 is that all A,B & C pistons and seals are the same except in the new replacement "C" calipers which take kit # 583-110. Those are the ones I would suspect are the metric size. Sorry I don't have any metric ones here to measure.
  I installed the 583-001 kits in the calipers of my TR 3 in '06. Over the winter the brake fluid leaked from the left caliper. I disassembled it and found the seal nearly turned to mush. I called Moss about it. The parts person I spoke to said they no longer sell it due to quality problems. I would suggest not using the kits with that part # unless you are sure they are genuine Girling and not el-cheapo brand.

Ken Suhre