This easy project will take little skill and almost no tools. Materials were bought from the local big box hardware store. The furnace humidifier aisle should have most of what you need. The solenoid valve and low voltage transformer are plug and play with no soldering. The saddle valve is how you can get the water. I tapped into the ice maker supply behind the fridge so that part was already installed.
The Transformer needed a switch so this cord did the trick. I eventually replaced the switch on the cord with a button. This was to prevent the water being left on. No finger on the button, no water. The tank is full in less than 10 seconds.
The tank has a molded finger grab. I slipped the hose in at that point, under the lid. Added the 90° elbow and another small hose to direct the water to the bottom of the tank.
There was no modification to the coffee machine.
Total cost was $75