I am about 1100 hours on this printer, so I guess it's not too bad that it lasted this long.

Still the plastic is far too thin for the amount of tension that it holds. I was able to use my 3D pen to piece it back together, but I will get a replacement from xyzprinting and reinforce it with extra ABS plastic.

Or better yet, the replacement models on thingiverse with bearings look like the way to go.

Unload your filament and unplug your printer.
Lift the top door and you can easily pop the side panels off by prying the top in a few places.
Taking them off is not necessary, but the open access will help a lot.
Use the flat head to remove the panel at the bottom of your door and disconnect the door sensor before removing it completely. (I took this opportunity to mush a ball of foil into the male connector, thereby closing the circuit for the door sensor. I did not reconnect the plug afterwards. No more annoying warning when I open it during a print!)
In each corner of the interior, there is a single screw holding the bottom plastic to the metal base.
Remove each one and then GENTLY lay your printer on its back. You should move the carriage all the way to the back before doing this, just so it doesn't freefall.
Each side of the printer will have 2 plastic tabs that you will use the flat head screwdriver to pry just a bit. Apply some tension to one corner as you do it, and they will each give a little "pop" when you get them.
Work from one corner, along each adjacent side, and down to the opposite corner. (if you start at the top left, end at the bottom right)
After all tabs have been popped, give a tug and the bottom should come off.
DON'T MOVE IT VERY FAR.
There are two connectors that you'll need to manage the wires for. One is your door sensor, the other is for your z-axis stepper motor.
If you can find the screw without unplugging the stepper motor, that's great. Mine disconnected, and I had to redo it. I avoided using the originally intended route, which causes the connector to have to go under a piece of the bottom panel. I just ran it straight to the motor.
Reassemble in reverse order!

Hopefully you can hear the screw before ever trying any of this. If you don't hear it, don't bother.

There aren't too many places for it to end up in a close box, but you never know.