Easier to access if you remove the side panel in the udc instead of the smaller one recommended by the factory, if your model is like mine, there are 5 valves, thats including the pump valve used to suck antifreeze out of the bottle. Some are hard to find, tucked under other wireing and water lines, i marked ours with different colored tape, red for hot, blue cold ext....good luck, if you hve any trouble pm me, i hve been in that area many many times!!