This master cylinder is made by TRW/Lucas. We can get the AP but it is more expensive. Both work just fine. Of course this is the cylinder for both brake and clutch. You can use regular brake fluid or silicone fluid. I use silicone because it does not affect the paint like regular brake fluid does. The bore [7/8"] on this cylinder is for drum brakes. If you have put disc brakes on the front you will have to change the master cylinder to the later unit, which has a bore dia. of 3/4".
Brake Master Cylinder - 1958 - 1963 - Spridget