The metered fill SQ washers used pressure switches, as above. They still used a restricted water valve like the time-fill models to control the rate of flow into the machine. Replacing the valve with an unrestricted type will throw off the "measuring" system.
Once you get the machine hooked up and water flows through it's normal system, it may work just fine though replacing the hose from the tank to the pressure switch would be a good preventative step. With the separate tank outside the main tub, filling with a hose or bucket only makes for fun spin-out.