Brake Fluid Reservoirs
A bare master cylinder requires a remote reservoir. These aluminum reservoirs replace the original plastic one and are mounted where the fluid level remains above the cylinder, which is essential for completing the bleeding process.
One reservoir per circuit
On a pedal box with two brake master cylinders, you need two: the front and rear circuits are independent, and feeding them from a shared reservoir defeats the independence you chose the system for.
Installation
Use a supply hose with the appropriate diameter and route it so it continuously slopes down toward the cylinder: a high loop traps air and makes bleeding endless.