Important: Before unscrewing the button and control board you must carefully remove all the plastic knobs from the top control surface. I used a pinching motion to pull the knobs away without bending them side to side. If they are very tight try warming them up a bit, gentle heat, like 105F

After removing all the knobs, unscrew the six silver screws

Carefully remove the buttons & controls board. If it's stuck you can push on the knob stems and buttons from the top

On the bottom of the PCB there are lots of black clips that correspond to the button housings and LED housings on the top of the board. Unclip to remove only if you need to