I'm going to add a dual reservoir to my 66 Cyclone 4 wheel drum brakes. Seems elementary. Dual cylinder for drum brakes. Disconnect the rear line from the 3 way block and bring it to the MC. Disconncet the line from the MC that feeds the left front and route it the 3 way block. No proportioning valve? Aren't the pressures from the dual reservoir cylinder for drum brakes equal?