(the one you bought at Sam’s Club)
Remove both of the screws marked with red arrows.
Remove either pair of the screws marked with green or yellow arrows (or both pairs, but then the whole thing falls apart and goes bang.)
Push down on the down arrow side and up on the up arrow side to unhook the little plastic hook thing.
If you still have the P50 instead of the P80, visit John’s blog instead.
The instructions were an excellent help to me. I would just add that on my model, it only required that I take one screw off of the side that I wanted to remove. For me it was the top green (as shown in the photo above), after I removed the two red screws.
Comment by Pete Allison — August 29, 2017 @ 2:59 pm