Dissecting the Yamaha AW16G - A very basic description
Remove all of the screws on the case except those indicated in the photos above and below.
Set the unit face down on some foam or a thick towel folded several times to avoid putting too much pressure on the stems of the control pots. Once the screws are removed, slide the bottom panel up a bit and open it like you would a book. Support the right "page" on a couple of 2x4" blocks and disconnect the ribbon connectors. They will pull out without too much resistance. Again, be gentle.
Remove the two screws holding in the patch board. Note that they are different from the other screws.
Remove every screw you can find. Note some are longer than others, and the ones along the edges are machine threaded. Make sure they get back in the right place. Also, be sure to keep track of the two grounding strips. They are different, and it matters which side they go on.
If you haven't already, remove the four screws holding the LCD board in place. Disconnect the power supply, then disconnect the ribbon connectors. See detail below first.
The LCD ribbon is held in place by a pinch bar. Just push it in the direction of the arrows and the cable will slide right out. Do this with both connectors. When re-installing, make sure the pinch bar is in the out position, insert the cable, and push the bar in. It should hold the cable nice and snug.
With all the screws removed, the remaining component boards will lift right out. If it is necessary to remove the side panels or the button panel, you can do so now. Be advised that they are held in place by some pretty strong adhesive in the areas indicated. Gentle, steady pressure will free them.
As a little bonus to the curious, here's what the control board looks like face up. Each pot and button is clearly labelled as to its function, so guesswork is eliminated. To reassemble the unit, follow these directions in reverse. Hope you enjoyed the show, and good luck!