Hey guys,   56 Mercury has a single master cylinder and a vacuum booster, not sure if the booster is stock or not (don't really even understand how it works).  Need to replace the rear wheel cylinders this winter, as they are leaking a bit, didn't know that until the single master ran out of fluid, real fun...   Looking to put in a new dual master cylinder while im at it.   Should i be replacing the booster too with a combo kit?    Heres whats in the car now.


Heres what im looking at. - https://www.speedwaymotors.com/Dual-7-Inch-Brake-Booster-Master-Cylinder-Combo-1-1-8-Inch-Bore,36378.html