This is a pair of cylinders from a Rolls-Royce Silver Cloud II. These are different in function than just about any other cylinder out there. In most systems the piston has a seal on the end that pressurizes the brake fluid between the seal on the end of the piston and the bore of the cylinder body. On this type the pressure seal is mounted in the body of the cylinder and the pressure is created between the piston surface and the seal in the body. Therefore the piston surface must be perfect in order for the cylinder to work properly. I see quite a few of these with the body sleeved but the old piston is put back in, then the cylinder starts to leak again soon after it's put back into the car. I either make a new piston from stainless or sleeve the old one in stainless if it is not in perfect condition.

This is the small (.750) bore cylinder as it arrived in the shop.

This is the larger (.980) bore cylinder.

Setting up a cylinder in the lathe.

Boring a cylinder on the lathe.

These are setting jigs I made for inserting the sleeves in these cylinders.
They ensure correct placement of the sleeves in the bores.